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<html> <head> <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> <meta name="ProgId" content="Word.Document"> <meta name="Originator" content="Microsoft Word 9"> <meta name="GENERATOR" content="Microsoft FrontPage Express 2.0"> <title>Computing Health Expectancies using IMaCh</title> <link rel="File-List" href="./imach_fichiers/filelist.xml"> <link rel="Edit-Time-Data" href="./imach_fichiers/editdata.mso">    <style>  </style>    </head> <body bgcolor="#FFFFFF" link="#0000FF" vlink="#0000FF" lang="FR" style="tab-interval:35.4pt"> <hr size="3" noshade color="#EC5E5E"> <h1 align="center" style="text-align:center">Computing Health Expectancies using IMaCh<o:p></o:p></h1> <h1 align="center" style="text-align:center">(a Maximum Likelihood Computer Program using Interpolation of Markov Chains)<o:p></o:p></h1>  <o:p></o:p> <a href="http://www.ined.fr/"><img src="logo-ined.gif" border="0" width="151" height="76" id="_x0000_i1026"></a><img src="euroreves2.gif" width="151" height="75" id="_x0000_i1027"> <h3 align="center" style="text-align:center"><a href="http://www.ined.fr/">INED</a> and <a href="http://euroreves.ined.fr">EUROREVES<o:p></o:p></a></h3> Version 0.7, February 2002<o:p></o:p> <hr size="3" noshade color="#EC5E5E"> Authors of the program: <a href="http://sauvy.ined.fr/brouard">Nicolas Brouard</a>, senior researcher at the <a href="http://www.ined.fr">Institut National d'Etudes D�mographiques</a> (INED, Paris) in the "Mortality, Health and Epidemiology" Research Unit <o:p></o:p> and Agn�s Li�vre <o:p></o:p> <h4>Contribution to the mathematics: C. R. Heathcote (Australian National University, Canberra).<o:p></o:p></h4> <h4>Contact: Agn�s Li�vre (<a href="mailto:lievre@ined.fr">lievre@ined.fr</a>) </h4> <hr> <ul type="disc"> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l17 level1 lfo3;tab-stops:list 36.0pt"><a href="#intro">Introduction</a> <o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l17 level1 lfo3;tab-stops:list 36.0pt"><a href="#data">On what kind of data can it be used?<o:p></o:p></a></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l17 level1 lfo3;tab-stops:list 36.0pt"><a href="#datafile">The data file</a> <o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l17 level1 lfo3;tab-stops:list 36.0pt"><a href="#biaspar">The parameter file</a> <o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l17 level1 lfo3;tab-stops:list 36.0pt"><a href="#running">Running Imach</a> <o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l17 level1 lfo3;tab-stops:list 36.0pt"><a href="#output">Output files and graphs</a> <o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l17 level1 lfo3;tab-stops:list 36.0pt"><a href="#example">Exemple</a> </li> </ul> <hr> <h2><a name="intro">Introduction<o:p></o:p></a></h2> This program computes Healthy Life Expectancies from cross-longitudinal data using the methodology pioneered by Laditka and Wolf (1). Within the family of Health Expectancies (HE), Disability-free life expectancy (DFLE) is probably the most important index to monitor. In low mortality countries, there is a fear that when mortality declines, the increase in DFLE is not proportionate to the increase in total Life expectancy. This case is called the Expansion of morbidity. Most of the data collected today, in particular by the international <a href="http://euroreves/reves">REVES</a> network on Health expectancy, and most HE indices based on these data, are cross-sectional. It means that the information collected comes from a single cross-sectional survey: people from various ages (but mostly old people) are surveyed on their health status at a single date. Proportion of people disabled at each age, can then be measured at that date. This age-specific prevalence curve is then used to distinguish, within the stationary population (which, by definition, is the life table estimated from the vital statistics on mortality at the same date), the disable population from the disability-free population. Life expectancy (LE) (or total population divided by the yearly number of births or deaths of this stationary population) is then decomposed into DFLE and DLE. This method of computing HE is usually called the Sullivan method (from the name of the author who first described it).<o:p></o:p> Age-specific proportions of people disable are very difficult to forecast because each proportion corresponds to historical conditions of the cohort and it is the result of the historical flows from entering disability and recovering in the past until today. The age-specific intensities (or incidence rates) of entering disability or recovering a good health, are reflecting actual conditions and therefore can be used at each age to forecast the future of this cohort. For example if a country is improving its technology of prosthesis, the incidence of recovering the ability to walk will be higher at each (old) age, but the prevalence of disability will only slightly reflect an improve because the prevalence is mostly affected by the history of the cohort and not by recent period effects. To measure the period improvement we have to simulate the future of a cohort of new-borns entering or leaving at each age the disability state or dying according to the incidence rates measured today on different cohorts. The proportion of people disabled at each age in this simulated cohort will be much lower (using the example of an improvement) that the proportions observed at each age in a cross-sectional survey. This new prevalence curve introduced in a life table will give a much more actual and realistic HE level than the Sullivan method which mostly measured the History of health conditions in this country.<o:p></o:p> Therefore, the main question is how to measure incidence rates from cross-longitudinal surveys? This is the goal of the IMaCH program. From your data and using IMaCH you can estimate period HE and not only Sullivan's HE. Also the standard errors of the HE are computed.<o:p></o:p> A cross-longitudinal survey consists in a first survey ("cross") where individuals from different ages are interviewed on their health status or degree of disability. At least a second wave of interviews ("longitudinal") should measure each new individual health status. Health expectancies are computed from the transitions observed between waves and are computed for each degree of severity of disability (number of life states). More degrees you consider, more time is necessary to reach the Maximum Likelihood of the parameters involved in the model. Considering only two states of disability (disable and healthy) is generally enough but the computer program works also with more health statuses.        The simplest model is the multinomial logistic model where pij is the probability to be observed in state j at the second wave conditional to be observed in state i at the first wave. Therefore a simple model is: log(pij/pii)= aij + bij*age+ cij*sex, where 'age' is age and 'sex' is a covariate. The advantage that this computer program claims, comes from that if the delay between waves is not identical for each individual, or if some individual missed an interview, the information is not rounded or lost, but taken into account using an interpolation or extrapolation. hPijx is the probability to be observed in state i at age x+h conditional to the observed state i at age x. The delay 'h' can be split into an exact number (nh*stepm) of unobserved intermediate states. This elementary transition (by month or quarter trimester, semester or year) is modeled as a multinomial logistic. The hPx matrix is simply the matrix product of nh*stepm elementary matrices and the contribution of each individual to the likelihood is simply hPijx. <o:p></o:p> The program presented in this manual is a quite general program named IMaCh (for Interpolated MArkov CHain), designed to analyse transition data from longitudinal surveys. The first step is the parameters estimation of a transition probabilities model between an initial status and a final status. From there, the computer program produces some indicators such as observed and stationary prevalence, life expectancies and their variances and graphs. Our transition model consists in absorbing and non-absorbing states with the possibility of return across the non-absorbing states. The main advantage of this package, compared to other programs for the analysis of transition data (For example: Proc Catmod of SAS(r)) is that the whole individual information is used even if an interview is missing, a status or a date is unknown or when the delay between waves is not identical for each individual. The program can be executed according to parameters: selection of a sub-sample, number of absorbing and non-absorbing states, number of waves taken in account (the user inputs the first and the last interview), a tolerance level for the maximization function, the periodicity of the transitions (we can compute annual, quarterly or monthly transitions), covariates in the model. It works on Windows or on Unix.<o:p></o:p> <hr> (1) Laditka, Sarah B. and Wolf, Douglas A. (1998), "New Methods for Analyzing Active Life Expectancy". Journal of Aging and Health. Vol 10, No. 2. <hr> <h2><a name="data">On what kind of data can it be used?<o:p></o:p></a></h2> The minimum data required for a transition model is the recording of a set of individuals interviewed at a first date and interviewed again at least one another time. From the observations of an individual, we obtain a follow-up over time of the occurrence of a specific event. In this documentation, the event is related to health status at older ages, but the program can be applied on a lot of longitudinal studies in different contexts. To build the data file explained into the next section, you must have the month and year of each interview and the corresponding health status. But in order to get age, date of birth (month and year) is required (missing values is allowed for month). Date of death (month and year) is an important information also required if the individual is dead. Shorter steps (i.e. a month) will more closely take into account the survival time after the last interview.<o:p></o:p> <hr> <h2><a name="datafile">The data file<o:p></o:p></a></h2> In this example, 8,000 people have been interviewed in a cross-longitudinal survey of 4 waves (1984, 1986, 1988, 1990). Some people missed 1, 2 or 3 interviews. Health statuses are healthy (1) and disable (2). The survey is not a real one. It is a simulation of the American Longitudinal Survey on Aging. The disability state is defined if the individual missed one of four ADL (Activity of daily living, like bathing, eating, walking). Therefore, even is the individuals interviewed in the sample are virtual, the information brought with this sample is close to the situation of the United States. Sex is not recorded is this sample.<o:p></o:p> Each line of the data set (named <a href="data1.txt">data1.txt</a> in this first example) is an individual record which fields are: <o:p></o:p> <ul type="disc"> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l12 level1 lfo6;tab-stops:list 36.0pt">Index number: positive number (field 1) <o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l12 level1 lfo6;tab-stops:list 36.0pt">First covariate positive number (field 2) <o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l12 level1 lfo6;tab-stops:list 36.0pt">Second covariate positive number (field 3) <o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l12 level1 lfo6;tab-stops:list 36.0pt"><a name="Weight">Weight</a>: positive number (field 4) . In most surveys individuals are weighted according to the stratification of the sample.<o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l12 level1 lfo6;tab-stops:list 36.0pt">Date of birth: coded as mm/yyyy. Missing dates are coded as 99/9999 (field 5) <o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l12 level1 lfo6;tab-stops:list 36.0pt">Date of death: coded as mm/yyyy. Missing dates are coded as 99/9999 (field 6) <o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l12 level1 lfo6;tab-stops:list 36.0pt">Date of first interview: coded as mm/yyyy. Missing dates are coded as 99/9999 (field 7) <o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l12 level1 lfo6;tab-stops:list 36.0pt">Status at first interview: positive number. Missing values ar coded -1. (field 8) <o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l12 level1 lfo6;tab-stops:list 36.0pt">Date of second interview: coded as mm/yyyy. Missing dates are coded as 99/9999 (field 9) <o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l12 level1 lfo6;tab-stops:list 36.0pt">Status at second interview positive number. Missing values ar coded -1. (field 10) <o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l12 level1 lfo6;tab-stops:list 36.0pt">Date of third interview: coded as mm/yyyy. Missing dates are coded as 99/9999 (field 11) <o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l12 level1 lfo6;tab-stops:list 36.0pt">Status at third interview positive number. Missing values ar coded -1. (field 12) <o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l12 level1 lfo6;tab-stops:list 36.0pt">Date of fourth interview: coded as mm/yyyy. Missing dates are coded as 99/9999 (field 13) <o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l12 level1 lfo6;tab-stops:list 36.0pt">Status at fourth interview positive number. Missing values are coded -1. (field 14) <o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l12 level1 lfo6;tab-stops:list 36.0pt">etc<o:p></o:p></li> </ul>  <o:p></o:p> If your longitudinal survey do not include information about weights or covariates, you must fill the column with a number (e.g. 1) because a missing field is not allowed.<o:p></o:p> <hr> <h2>Your first example parameter file<a href="http://euroreves.ined.fr/imach"></a><a name="uio"><o:p></o:p></a></h2> <h2><a name="biaspar"></a>#Imach version 0.7, February 2002, INED-EUROREVES <o:p></o:p></h2> This is a comment. Comments start with a '#'.<o:p></o:p> <h4>First uncommented line<o:p></o:p></h4> <pre style="text-align:justify">title=1st_example datafile=data1.txt lastobs=8600 firstpass=1 lastpass=4<o:p></o:p></pre> <ul type="disc"> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l1 level1 lfo9;tab-stops:list 36.0pt">title= 1st_example is title of the run. <o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l1 level1 lfo9;tab-stops:list 36.0pt">datafile=data1.txt is the name of the data set. Our example is a six years follow-up survey. It consists in a baseline followed by 3 reinterviews. <o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l1 level1 lfo9;tab-stops:list 36.0pt">lastobs= 8600 the program is able to run on a subsample where the last observation number is lastobs. It can be set a bigger number than the real number of observations (e.g. 100000). In this example, maximisation will be done on the 8600 first records. <o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l1 level1 lfo9;tab-stops:list 36.0pt">firstpass=1 , lastpass=4 In case of more than two interviews in the survey, the program can be run on selected transitions periods. firstpass=1 means the first interview included in the calculation is the baseline survey. lastpass=4 means that the information brought by the 4th interview is taken into account.<o:p></o:p></li> </ul>  <o:p></o:p> <h4 style="text-align:justify;tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt">Second uncommented line<a name="biaspar-2"><o:p></o:p></a></h4> <pre style="text-align:justify">ftol=1.e-08 stepm=1 ncov=2 nlstate=2 ndeath=1 maxwav=4 mle=1 weight=0<o:p></o:p></pre> <ul type="disc"> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l14 level1 lfo12;tab-stops:list 36.0pt">ftol=1e-8 Convergence tolerance on the function value in the maximisation of the likelihood. Choosing a correct value for ftol is difficult. 1e-8 is a correct value for a 32 bits computer.<o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l14 level1 lfo12;tab-stops:list 36.0pt">stepm=1 Time unit in months for interpolation. Examples:<o:p></o:p></li> <li><ul type="circle"> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt: auto;text-align:justify;mso-list:l14 level2 lfo12;tab-stops:list 72.0pt">If stepm=1, the unit is a month <o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt: auto;text-align:justify;mso-list:l14 level2 lfo12;tab-stops:list 72.0pt">If stepm=4, the unit is a trimester<o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt: auto;text-align:justify;mso-list:l14 level2 lfo12;tab-stops:list 72.0pt">If stepm=12, the unit is a year <o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt: auto;text-align:justify;mso-list:l14 level2 lfo12;tab-stops:list 72.0pt">If stepm=24, the unit is two years<o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt: auto;text-align:justify;mso-list:l14 level2 lfo12;tab-stops:list 72.0pt">... <o:p></o:p> </li> </ul> </li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l14 level1 lfo12;tab-stops:list 36.0pt">ncov=2 Number of covariates in the datafile. The intercept and the age parameter are counting for 2 covariates.<o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l14 level1 lfo12;tab-stops:list 36.0pt">nlstate=2 Number of non-absorbing (alive) states. Here we have two alive states: disability-free is coded 1 and disability is coded 2. <o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l14 level1 lfo12;tab-stops:list 36.0pt">ndeath=1 Number of absorbing states. The absorbing state death is coded 3. <o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l14 level1 lfo12;tab-stops:list 36.0pt">maxwav=4 Number of waves in the datafile.<o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l14 level1 lfo12;tab-stops:list 36.0pt"><a name="mle">mle</a>=1 Option for the Maximisation Likelihood Estimation. <o:p></o:p></li> <li><ul type="circle"> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt: auto;text-align:justify;mso-list:l14 level2 lfo12;tab-stops:list 72.0pt">If mle=1 the program does the maximisation and the calculation of health expectancies <o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt: auto;text-align:justify;mso-list:l14 level2 lfo12;tab-stops:list 72.0pt">If mle=0 the program only does the calculation of the health expectancies. <o:p></o:p></li> </ul> </li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l14 level1 lfo12;tab-stops:list 36.0pt">weight=0 Possibility to add weights. <o:p></o:p></li> <li><ul type="circle"> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt: auto;text-align:justify;mso-list:l14 level2 lfo12;tab-stops:list 72.0pt">If weight=0 no weights are included <o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt: auto;text-align:justify;mso-list:l14 level2 lfo12;tab-stops:list 72.0pt">If weight=1 the maximisation integrates the weights which are in field <a href="#Weight">4<o:p></o:p></a></li> </ul> </li> </ul> <h4 style="text-align:justify;tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt">Covariates<o:p></o:p></h4> Intercept and age are systematically included in the model. Additional covariates can be included with the command <o:p></o:p> <pre style="text-align:justify">model=list of covariates<o:p></o:p></pre> <ul type="disc"> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l2 level1 lfo15;tab-stops:list 36.0pt">if model=. then no covariates are included<o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l2 level1 lfo15;tab-stops:list 36.0pt">if model=V1 the model includes the first covariate (field 2)<o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l2 level1 lfo15;tab-stops:list 36.0pt">if model=V2 the model includes the second covariate (field 3)<o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l2 level1 lfo15;tab-stops:list 36.0pt">if model=V1+V2 the model includes the first and the second covariate (fields 2 and 3)<o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l2 level1 lfo15;tab-stops:list 36.0pt">if model=V1*V2 the model includes the product of the first and the second covariate (fields 2 and 3)<o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l2 level1 lfo15;tab-stops:list 36.0pt">if model=V1+V1*age the model includes the product covariate*age<o:p></o:p></li> </ul> <h4 style="text-align:justify;tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt">Guess values for optimisation <o:p></o:p></h4> You must write the initial guess values of the parameters for optimisation. The number of parameters, N depends on the number of absorbing states and non-absorbing states and on the number of covariates. N is given by the formula N=(nlstate + ndeath-1)*nlstate*ncov . Thus in the simple case with 2 covariates (the model is log (pij/pii) = aij + bij * age where intercept and age are the two covariates), and 2 health degrees (1 for disability-free and 2 for disability) and 1 absorbing state (3), you must enter 8 initials values, a12, b12, a13, b13, a21, b21, a23, b23. You can start with zeros as in this example, but if you have a more precise set (for example from an earlier run) you can enter it and it will speed up them Each of the four lines starts with indices "ij": ij aij bij <o:p></o:p> <pre style="margin-top:0cm;margin-right:36.0pt;margin-bottom:0cm;margin-left: 36.0pt;margin-bottom:.0001pt;text-align:justify"># Guess values of aij and bij in log (pij/pii) = aij + bij * age<o:p></o:p></pre> <pre style="margin-top:0cm;margin-right:36.0pt;margin-bottom:0cm;margin-left:36.0pt; margin-bottom:.0001pt;text-align:justify">12 -14.155633  0.110794 <o:p></o:p></pre> <pre style="margin-top:0cm;margin-right:36.0pt;margin-bottom:0cm;margin-left:36.0pt; margin-bottom:.0001pt;text-align:justify">13  -7.925360  0.032091 <o:p></o:p></pre> <pre style="margin-top:0cm;margin-right:36.0pt;margin-bottom:0cm;margin-left:36.0pt; margin-bottom:.0001pt;text-align:justify">21  -1.890135 -0.029473 <o:p></o:p></pre> <pre style="margin-top:0cm;margin-right:36.0pt;margin-bottom:0cm;margin-left:36.0pt; margin-bottom:.0001pt;text-align:justify">23  -6.234642  0.022315 <o:p></o:p></pre> or, to simplify: <o:p></o:p> <pre style="margin-top:0cm;margin-right:36.0pt;margin-bottom:0cm;margin-left: 36.0pt;margin-bottom:.0001pt;text-align:justify">12 0.0 0.0<o:p></o:p></pre> <pre style="margin-top:0cm;margin-right:36.0pt;margin-bottom:0cm;margin-left:36.0pt; margin-bottom:.0001pt;text-align:justify">13 0.0 0.0<o:p></o:p></pre> <pre style="margin-top:0cm;margin-right: 36.0pt;margin-bottom:0cm;margin-left:36.0pt;margin-bottom:.0001pt;text-align: justify">21 0.0 0.0<o:p></o:p></pre> <pre style="margin-top:0cm;margin-right:36.0pt;margin-bottom:0cm;margin-left:36.0pt; margin-bottom:.0001pt;text-align:justify">23 0.0 0.0<o:p></o:p></pre> <h4 style="text-align:justify;tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt">Guess values for computing variances<o:p></o:p></h4> This is an output if <a href="#mle">mle</a>=1. But it can be used as an input to get the various output data files (Health expectancies, stationary prevalence etc.) and figures without rerunning the rather long maximisation phase (mle=0). <o:p></o:p> The scales are small values for the evaluation of numerical derivatives. These derivatives are used to compute the hessian matrix of the parameters, that is the inverse of the covariance matrix, and the variances of health expectancies. Each line consists in indices "ij" followed by the initial scales (zero to simplify) associated with aij and bij. <o:p></o:p> <ul type="disc"> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l16 level1 lfo18;tab-stops:list 36.0pt">If mle=1 you can enter zeros:<o:p></o:p></li> </ul> <pre style="margin-top:0cm;margin-right:36.0pt;margin-bottom:0cm;margin-left: 36.0pt;margin-bottom:.0001pt;text-align:justify"># Scales (for hessian or gradient estimation)<o:p></o:p></pre> <pre style="margin-top:0cm;margin-right:36.0pt;margin-bottom:0cm;margin-left:36.0pt; margin-bottom:.0001pt;text-align:justify">12 0. 0. <o:p></o:p></pre> <pre style="margin-top:0cm;margin-right: 36.0pt;margin-bottom:0cm;margin-left:36.0pt;margin-bottom:.0001pt;text-align: justify">13 0. 0. <o:p></o:p></pre> <pre style="margin-top:0cm;margin-right:36.0pt;margin-bottom:0cm;margin-left:36.0pt; margin-bottom:.0001pt;text-align:justify">21 0. 0. <o:p></o:p></pre> <pre style="margin-top:0cm;margin-right: 36.0pt;margin-bottom:0cm;margin-left:36.0pt;margin-bottom:.0001pt;text-align: justify">23 0. 0. <o:p></o:p></pre> <ul type="disc"> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l11 level1 lfo21;tab-stops:list 36.0pt">If mle=0 you must enter a covariance matrix (usually obtained from an earlier run).<o:p></o:p></li> </ul> <h4 style="text-align:justify;tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt">Covariance matrix of parameters<o:p></o:p></h4> This is an output if <a href="#mle">mle</a>=1. But it can be used as an input to get the various output data files (Health expectancies, stationary prevalence etc.) and figures without rerunning the rather long maximisation phase (mle=0). <o:p></o:p> Each line starts with indices "ijk" followed by the covariances between aij and bij: <o:p></o:p> <pre style="text-align:justify"> <o:p></o:p></pre> <pre style="text-align:justify">   121 Var(a12) <o:p></o:p></pre> <pre style="text-align:justify">   122 Cov(b12,a12)  Var(b12) <o:p></o:p></pre> <pre style="text-align:justify">          ...<o:p></o:p></pre> <pre style="text-align:justify">   232 Cov(b23,a12)  Cov(b23,b12) ... Var (b23) <o:p></o:p></pre> <ul type="disc"> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l18 level1 lfo24;tab-stops:list 36.0pt">If mle=1 you can enter zeros. <o:p></o:p></li> </ul> <pre style="margin-top:0cm;margin-right:36.0pt;margin-bottom:0cm;margin-left: 36.0pt;margin-bottom:.0001pt;text-align:justify"># Covariance matrix<o:p></o:p></pre> <pre style="margin-top:0cm;margin-right:36.0pt;margin-bottom:0cm;margin-left:36.0pt; margin-bottom:.0001pt;text-align:justify">121 0.<o:p></o:p></pre> <pre style="margin-top:0cm;margin-right: 36.0pt;margin-bottom:0cm;margin-left:36.0pt;margin-bottom:.0001pt;text-align: justify">122 0. 0.<o:p></o:p></pre> <pre style="margin-top:0cm;margin-right:36.0pt;margin-bottom:0cm;margin-left:36.0pt; margin-bottom:.0001pt;text-align:justify">131 0. 0. 0. <o:p></o:p></pre> <pre style="margin-top:0cm; margin-right:36.0pt;margin-bottom:0cm;margin-left:36.0pt;margin-bottom:.0001pt; text-align:justify">132 0. 0. 0. 0. <o:p></o:p></pre> <pre style="margin-top:0cm;margin-right:36.0pt;margin-bottom:0cm;margin-left:36.0pt; margin-bottom:.0001pt;text-align:justify">211 0. 0. 0. 0. 0. <o:p></o:p></pre> <pre style="margin-top:0cm; margin-right:36.0pt;margin-bottom:0cm;margin-left:36.0pt;margin-bottom:.0001pt; text-align:justify">212 0. 0. 0. 0. 0. 0. <o:p></o:p></pre> <pre style="margin-top:0cm;margin-right:36.0pt;margin-bottom:0cm;margin-left:36.0pt; margin-bottom:.0001pt;text-align:justify">231 0. 0. 0. 0. 0. 0. 0. <o:p></o:p></pre> <pre style="margin-top: 0cm;margin-right:36.0pt;margin-bottom:0cm;margin-left:36.0pt;margin-bottom: .0001pt;text-align:justify">232 0. 0. 0. 0. 0. 0. 0. 0.<o:p></o:p></pre> <ul type="disc"> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l7 level1 lfo27;tab-stops:list 36.0pt">If mle=0 you must enter a covariance matrix (usually obtained from an earlier run).<o:p></o:p></li> </ul> <h4 style="text-align:justify;tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt">Age range for calculation of stationary prevalences and health expectancies<o:p></o:p></h4> <pre style="text-align:justify">agemin=70 agemax=100 bage=50 fage=100<o:p></o:p></pre> Once we obtained the estimated parameters, the program is able to calculated stationary prevalence, transitions probabilities and life expectancies at any age. Choice of age range is useful for extrapolation. In our data file, ages varies from age 70 to 102. Setting bage=50 and fage=100, makes the program computing life expectancy from age bage to age fage. As we use a model, we can compute life expectancy on a wider age range than the age range from the data. But the model can be rather wrong on big intervals.<o:p></o:p> Similarly, it is possible to get extrapolated stationary prevalence by age ranging from agemin to agemax. <o:p></o:p> <ul type="disc"> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l13 level1 lfo30;tab-stops:list 36.0pt">agemin= Minimum age for calculation of the stationary prevalence <o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l13 level1 lfo30;tab-stops:list 36.0pt">agemax= Maximum age for calculation of the stationary prevalence <o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l13 level1 lfo30;tab-stops:list 36.0pt">bage= Minimum age for calculation of the health expectancies <o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l13 level1 lfo30;tab-stops:list 36.0pt">fage= Maximum age for calculation of the health expectancies <o:p></o:p></li> </ul> <h4 style="text-align:justify;tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><a name="Computing">Computing</a> the observed prevalence<o:p></o:p></h4> <pre style="text-align:justify">begin-prev-date=1/1/1984 end-prev-date=1/6/1988 <o:p></o:p></pre> Statements 'begin-prev-date' and 'end-prev-date' allow to select the period in which we calculate the observed prevalences in each state. In this example, the prevalences are calculated on data survey collected between 1 January 1984 and 1 June 1988. <o:p></o:p> <ul type="disc"> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l3 level1 lfo33;tab-stops:list 36.0pt">begin-prev-date= Starting date (day/month/year)<o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l3 level1 lfo33;tab-stops:list 36.0pt">end-prev-date= Final date (day/month/year)<o:p></o:p></li> </ul> <h4 style="text-align:justify;tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt">Population- or status-based health expectancies<o:p></o:p></h4> <pre style="text-align:justify">pop_based=0<o:p></o:p></pre> The user has the possibility to choose between population-based or status-based health expectancies. If pop_based=0 then status-based health expectancies are computed and if pop_based=1, the programme computes population-based health expectancies. Health expectancies are weighted averages of health expectancies respective of the initial state. For a status-based index, the weights are the cross-sectional prevalences observed between two dates, as <a href="#Computing">previously explained</a>, whereas for a population-based index, the weights are the stationary prevalences.<o:p></o:p> <h4 style="text-align:justify;tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt">Prevalence forecasting <o:p></o:p></h4> <pre style="text-align:justify">starting-proj-date=1/1/1989 final-proj-date=1/1/1992 mov_average=0 <o:p></o:p></pre> Prevalence and population projections are available only if the interpolation unit is a month, i.e. stepm=1. The programme estimates the prevalence in each state at a precise date expressed in day/month/year. The programme computes one forecasted prevalence a year from a starting date (1 January of 1989 in this example) to a final date (1 January 1992). The statement mov_average allows to compute smoothed forecasted prevalences with a five-age moving average centred at the mid-age of the five-age period. <o:p></o:p> <ul type="disc"> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l10 level1 lfo36;tab-stops:list 36.0pt">starting-proj-date= starting date (day/month/year) of forecasting<o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l10 level1 lfo36;tab-stops:list 36.0pt">final-proj-date= final date (day/month/year) of forecasting<o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l10 level1 lfo36;tab-stops:list 36.0pt">mov_average= smoothing with a five-age moving average centred at the mid-age of the five-age period. The command mov_average takes value 1 if the prevalences are smoothed and 0 otherwise.<o:p></o:p></li> </ul> <h4 style="text-align:justify;tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt">Last uncommented line : Population forecasting <o:p></o:p></h4> <pre>popforecast=0 popfile=pyram.txt popfiledate=1/1/1989 last-popfiledate=1/1/1992<o:p></o:p></pre> This command is available if the interpolation unit is a month, i.e. stepm=1 and if popforecast=1. From a data file including age and number of persons alive at the precise date popfiledate, you can forecast the number of persons in each state until date last-popfiledate. In this example, the popfile <a href="pyram.txt">pyram.txt</a>  includes real data which are the Japanese population in 1989.  <o:p></o:p> <ul type="disc"> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l10 level1 lfo36;tab-stops:list 36.0pt">popforecast= 0 Option for population forecasting. If popforecast=1, the programme does the forecasting.<o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l10 level1 lfo36;tab-stops:list 36.0pt">popfile= name of the population file<o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l10 level1 lfo36;tab-stops:list 36.0pt">popfiledate= date of the population population<o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l10 level1 lfo36;tab-stops:list 36.0pt">last-popfiledate= date of the last population projection <o:p></o:p></li> </ul> <hr> <h2 style="text-align:justify;tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><a name="running"></a>Running Imach with this example<o:p></o:p></h2> We assume that you entered your <a href="biaspar.imach">1st_example parameter file</a> as explained <a href="#biaspar">above</a>. To run the program you should click on the imach.exe icon and enter the name of the parameter file which is for example <a href="..\mle\biaspar.txt">C:\usr\imach\mle\biaspar.txt</a> (you also can click on the biaspar.txt icon located in <a href="..\mle">C:\usr\imach\mle</a> and put it with the mouse on the imach window).<o:p></o:p> The time to converge depends on the step unit that you used (1 month is cpu consuming), on the number of cases, and on the number of variables.<o:p></o:p> The program outputs many files. Most of them are files which will be plotted for better understanding.<o:p></o:p> <hr> <h2 style="text-align:justify;tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><a name="output">Output of the program and graphs</a> <o:p></o:p></h2> Once the optimization is finished, some graphics can be made with a grapher. We use Gnuplot which is an interactive plotting program copyrighted but freely distributed. A gnuplot reference manual is available <a href="http://www.gnuplot.info/">here</a>. When the running is finished, the user should enter a character for plotting and output editing. <o:p></o:p> These characters are:<o:p></o:p> <ul type="disc"> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l0 level1 lfo41;tab-stops:list 36.0pt">'c' to start again the program from the beginning.<o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l0 level1 lfo41;tab-stops:list 36.0pt">'e' opens the <a href="biaspar.htm">biaspar.htm</a> file to edit the output files and graphs. <o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; text-align:justify;mso-list:l0 level1 lfo41;tab-stops:list 36.0pt">'q' for exiting.<o:p></o:p></li> </ul> <h5 style="tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt">Results files - <a name="Observed_prevalence_in_each_state">Observed prevalence in each state</a> (and at first pass): <a href="prbiaspar.txt">prbiaspar.txt<o:p></o:p></a></h5> The first line is the title and displays each field of the file. The first column is age. The fields 2 and 6 are the proportion of individuals in states 1 and 2 respectively as observed during the first exam. Others fields are the numbers of people in states 1, 2 or more. The number of columns increases if the number of states is higher than 2. The header of the file is <o:p></o:p> <pre style="text-align:justify"># Age Prev(1) N(1) N Age Prev(2) N(2) N<o:p></o:p></pre> <pre style="text-align:justify">70 1.00000 631 631 70 0.00000 0 631<o:p></o:p></pre> <pre style="text-align:justify">71 0.99681 625 627 71 0.00319 2 627 <o:p></o:p></pre> <pre style="text-align:justify">72 0.97125 1115 1148 72 0.02875 33 1148 <o:p></o:p></pre> It means that at age 70, the prevalence in state 1 is 1.000 and in state 2 is 0.00 . At age 71 the number of individuals in state 1 is 625 and in state 2 is 2, hence the total number of people aged 71 is 625+2=627. <o:p></o:p> <h5 style="text-align:justify;tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt">- Estimated parameters and covariance matrix: <a href="rbiaspar.txt">rbiaspar.txt<o:p></o:p></a></h5> This file contains all the maximisation results: <o:p></o:p> <pre style="text-align:justify"> -2 log likelihood= 21660.918613445392<o:p></o:p></pre> <pre style="text-align:justify"> Estimated parameters: a12 = -12.290174 b12 = 0.092161 <o:p></o:p></pre> <pre style="text-align:justify">                       a13 = -9.155590  b13 = 0.046627 <o:p></o:p></pre> <pre style="text-align:justify">                       a21 = -2.629849  b21 = -0.022030 <o:p></o:p></pre> <pre style="text-align:justify">                       a23 = -7.958519  b23 = 0.042614  <o:p></o:p></pre> <pre style="text-align:justify"> Covariance matrix: Var(a12) = 1.47453e-001<o:p></o:p></pre> <pre style="text-align:justify">                    Var(b12) = 2.18676e-005<o:p></o:p></pre> <pre style="text-align:justify">                    Var(a13) = 2.09715e-001<o:p></o:p></pre> <pre style="text-align:justify">                    Var(b13) = 3.28937e-005  <o:p></o:p></pre> <pre style="text-align:justify">                    Var(a21) = 9.19832e-001<o:p></o:p></pre> <pre style="text-align:justify">                    Var(b21) = 1.29229e-004<o:p></o:p></pre> <pre style="text-align:justify">                    Var(a23) = 4.48405e-001<o:p></o:p></pre> <pre style="text-align:justify">                    Var(b23) = 5.85631e-005 <o:p></o:p></pre> <pre style="text-align:justify"> <o:p></o:p></pre> By substitution of these parameters in the regression model, we obtain the elementary transition probabilities:<o:p></o:p> <img src="pebiaspar1.gif" width="400" height="300" id="_x0000_i1037"> <h5 style="text-align:justify;tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt">- Transition probabilities: <a href="pijrbiaspar.txt">pijrbiaspar.txt<o:p></o:p></a></h5> Here are the transitions probabilities Pij(x, x+nh) where nh is a multiple of 2 years. The first column is the starting age x (from age 50 to 100), the second is age (x+nh) and the others are the transition probabilities p11, p12, p13, p21, p22, p23. For example, line 5 of the file is: <o:p></o:p> <pre style="text-align:justify"> 100 106 0.02655 0.17622 0.79722 0.01809 0.13678 0.84513 <o:p></o:p></pre> and this means: <o:p></o:p> <pre style="text-align:justify">p11(100,106)=0.02655<o:p></o:p></pre> <pre style="text-align:justify">p12(100,106)=0.17622<o:p></o:p></pre> <pre style="text-align:justify">p13(100,106)=0.79722<o:p></o:p></pre> <pre style="text-align:justify">p21(100,106)=0.01809<o:p></o:p></pre> <pre style="text-align:justify">p22(100,106)=0.13678<o:p></o:p></pre> <pre style="text-align:justify">p22(100,106)=0.84513 <o:p></o:p></pre> <h5 style="text-align:justify;tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt">- <a name="Stationary_prevalence_in_each_state">Stationary prevalence in each state</a>: <a href="plrbiaspar.txt">plrbiaspar.txt<o:p></o:p></a></h5> <pre style="text-align:justify">#Prevalence<o:p></o:p></pre> <pre style="text-align:justify">#Age 1-1 2-2<o:p></o:p></pre> <pre style="text-align:justify"> <o:p></o:p></pre> <pre style="text-align:justify">#************ <o:p></o:p></pre> <pre style="text-align:justify">70 0.90134 0.09866<o:p></o:p></pre> <pre style="text-align:justify">71 0.89177 0.10823 <o:p></o:p></pre> <pre style="text-align:justify">72 0.88139 0.11861 <o:p></o:p></pre> <pre style="text-align:justify">73 0.87015 0.12985 <o:p></o:p></pre> At age 70 the stationary prevalence is 0.90134 in state 1 and 0.09866 in state 2. This stationary prevalence differs from observed prevalence. Here is the point. The observed prevalence at age 70 results from the incidence of disability, incidence of recovery and mortality which occurred in the past of the cohort. Stationary prevalence results from a simulation with actual incidences and mortality (estimated from this cross-longitudinal survey). It is the best predictive value of the prevalence in the future if "nothing changes in the future". This is exactly what demographers do with a Life table. Life expectancy is the expected mean time to survive if observed mortality rates (incidence of mortality) "remains constant" in the future. <o:p></o:p> <h5 style="text-align:justify;tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt">- Standard deviation of stationary prevalence: <a href="vplrbiaspar.txt">vplrbiaspar.txt<o:p></o:p></a></h5> The stationary prevalence has to be compared with the observed prevalence by age. But both are statistical estimates and subjected to stochastic errors due to the size of the sample, the design of the survey, and, for the stationary prevalence to the model used and fitted. It is possible to compute the standard deviation of the stationary prevalence at each age.<o:p></o:p> <h5 style="text-align:justify;tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt">-Observed and stationary prevalence in state (2=disable) with the confident interval: <a href="vbiaspar21.htm">vbiaspar21.gif<o:p></o:p></a></h5> This graph exhibits the stationary prevalence in state (2) with the confidence interval in red. The green curve is the observed prevalence (or proportion of individuals in state (2)). Without discussing the results (it is not the purpose here), we observe that the green curve is rather below the stationary prevalence. It suggests an increase of the disability prevalence in the future.<o:p></o:p> <img src="vbiaspar21.gif" width="400" height="300" id="_x0000_i1038"> <h5 style="tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt">-Convergence to the stationary prevalence of disability: <a href="pbiaspar11.gif">pbiaspar11.gif</a> <img src="pbiaspar11.gif" width="400" height="300" id="_x0000_i1039"><o:p></o:p></h5> This graph plots the conditional transition probabilities from an initial state (1=healthy in red at the bottom, or 2=disable in green on top) at age x to the final state 2=disable at age x+h. Conditional means at the condition to be alive at age x+h which is hP12x + hP22x. The curves hP12x/(hP12x + hP22x) and hP22x/(hP12x + hP22x) converge with h, to the stationary prevalence of disability. In order to get the stationary prevalence at age 70 we should start the process at an earlier age, i.e.50. If the disability state is defined by severe disability criteria with only a few chance to recover, then the incidence of recovery is low and the time to convergence is probably longer. But we don't have experience yet.<o:p></o:p> <h5 style="text-align:justify;tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt">- Life expectancies by age and initial health status: <a href="erbiaspar.txt">erbiaspar.txt<o:p></o:p></a></h5> <pre style="text-align:justify"># Health expectancies <o:p></o:p></pre> <pre style="text-align:justify"># Age 1-1 1-2 2-1 2-2 <o:p></o:p></pre> <pre style="text-align:justify">70 10.9226 3.0401 5.6488 6.2122 <o:p></o:p></pre> <pre style="text-align:justify">71 10.4384 3.0461 5.2477 6.1599 <o:p></o:p></pre> <pre style="text-align:justify">72 9.9667 3.0502 4.8663 6.1025 <o:p></o:p></pre> <pre style="text-align:justify">73 9.5077 3.0524 4.5044 6.0401 <o:p></o:p></pre> <pre style="text-align:justify">For example 70 10.9226 3.0401 5.6488 6.2122 means:<o:p></o:p></pre> <pre style="text-align:justify">e11=10.9226 e12=3.0401 e21=5.6488 e22=6.2122<o:p></o:p></pre> <pre style="text-align:justify"><img src="expbiaspar21.gif" width="400" height="300" id="_x0000_i1040"><img src="expbiaspar11.gif" width="400" height="300" id="_x0000_i1041"></pre> For example, life expectancy of a healthy individual at age 70 is 10.92 in the healthy state and 3.04 in the disability state (=13.96 years). If he was disable at age 70, his life expectancy will be shorter, 5.64 in the healthy state and 6.21 in the disability state (=11.85 years). The total life expectancy is a weighted mean of both, 13.96 and 11.85; weight is the proportion of people disabled at age 70. In order to get a pure period index (i.e. based only on incidences) we use the <a href="#Stationary prevalence in each state">computed or stationary prevalence</a> at age 70 (i.e. computed from incidences at earlier ages) instead of the <a href="#Observed prevalence in each state">observed prevalence</a> (for example at first exam) (<a href="#Health expectancies">see below</a>).<o:p></o:p> <h5 style="text-align:justify;tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt">- Variances of life expectancies by age and initial health status: <a href="vrbiaspar.txt">vrbiaspar.txt<o:p></o:p></a></h5> For example, the covariances of life expectancies Cov(ei,ej) at age 50 are (line 3) <o:p></o:p> <pre style="text-align:justify">   Cov(e1,e1)=0.4776  Cov(e1,e2)=0.0488=Cov(e2,e1)  Cov(e2,e2)=0.0424<o:p></o:p></pre> <h5 style="text-align:justify;tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt">- <a name="Health_expectancies">Health expectancies</a> with standard errors in parentheses: <a href="trbiaspar.txt">trbiaspar.txt<o:p></o:p></a></h5> <pre style="text-align:justify">#Total LEs with variances: e.. (std) e.1 (std) e.2 (std) <o:p></o:p></pre> <pre style="text-align:justify">70 13.76 (0.22) 10.40 (0.20) 3.35 (0.14) <o:p></o:p></pre> Thus, at age 70 the total life expectancy, e..=13.76years is the weighted mean of e1.=13.96 and e2.=11.85 by the stationary prevalence at age 70 which are 0.90134 in state 1 and 0.09866 in state 2, respectively (the sum is equal to one). e.1=10.40 is the Disability-free life expectancy at age 70 (it is again a weighted mean of e11 and e21). e.2=3.35 is also the life expectancy at age 70 to be spent in the disability state.<o:p></o:p> <h5 style="text-align:justify;tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt">-Total life expectancy by age and health expectancies in states (1=healthy) and (2=disable): <a href="ebiaspar1.gif">ebiaspar1.gif<o:p></o:p></a></h5> This figure represents the health expectancies and the total life expectancy with the confident interval in dashed curve. <o:p></o:p> <pre style="text-align:justify">        <img src="ebiaspar1.gif" width="400" height="300" id="_x0000_i1042"></pre> Standard deviations (obtained from the information matrix of the model) of these quantities are very useful. Cross-longitudinal surveys are costly and do not involve huge samples, generally a few thousands; therefore it is very important to have an idea of the standard deviation of our estimates. It has been a big challenge to compute the Health Expectancy standard deviations. Don't be confuse: life expectancy is, as any expected value, the mean of a distribution; but here we are not computing the standard deviation of the distribution, but the standard deviation of the estimate of the mean.<o:p></o:p> Our health expectancies estimates vary according to the sample size (and the standard deviations give confidence intervals of the estimate) but also according to the model fitted. Let us explain it in more details.<o:p></o:p> Choosing a model means at least two kind of choices. First we have to decide the number of disability states. Second we have to design, within the logit model family, the model: variables, covariables, confounding factors etc. to be included.<o:p></o:p> More disability states we have, better is our demographical approach of the disability process, but smaller are the number of transitions between each state and higher is the noise in the measurement. We do not have enough experiments of the various models to summarize the advantages and disadvantages, but it is important to say that even if we had huge and unbiased samples, the total life expectancy computed from a cross-longitudinal survey, varies with the number of states. If we define only two states, alive or dead, we find the usual life expectancy where it is assumed that at each age, people are at the same risk to die. If we are differentiating the alive state into healthy and disable, and as the mortality from the disability state is higher than the mortality from the healthy state, we are introducing heterogeneity in the risk of dying. The total mortality at each age is the weighted mean of the mortality in each state by the prevalence in each state. Therefore if the proportion of people at each age and in each state is different from the stationary equilibrium, there is no reason to find the same total mortality at a particular age. Life expectancy, even if it is a very useful tool, has a very strong hypothesis of homogeneity of the population. Our main purpose is not to measure differential mortality but to measure the expected time in a healthy or disability state in order to maximise the former and minimize the latter. But the differential in mortality complexifies the measurement.<o:p></o:p> Incidences of disability or recovery are not affected by the number of states if these states are independant. But incidences estimates are dependant on the specification of the model. More covariates we added in the logit model better is the model, but some covariates are not well measured, some are confounding factors like in any statistical model. The procedure to "fit the best model' is similar to logistic regression which itself is similar to regression analysis. We haven't yet been so far because we also have a severe limitation which is the speed of the convergence. On a Pentium III, 500 MHz, even the simplest model, estimated by month on 8,000 people may take 4 hours to converge. Also, the program is not yet a statistical package, which permits a simple writing of the variables and the model to take into account in the maximisation. The actual program allows only to add simple variables like age+sex or age+sex+ age*sex but will never be general enough. But what is to remember, is that incidences or probability of change from one state to another is affected by the variables specified into the model.<o:p></o:p> Also, the age range of the people interviewed has a link with the age range of the life expectancy which can be estimated by extrapolation. If your sample ranges from age 70 to 95, you can clearly estimate a life expectancy at age 70 and trust your confidence interval which is mostly based on your sample size, but if you want to estimate the life expectancy at age 50, you should rely in your model, but fitting a logistic model on a age range of 70-95 and estimating probabilities of transition out of this age range, say at age 50 is very dangerous. At least you should remember that the confidence interval given by the standard deviation of the health expectancies, are under the strong assumption that your model is the 'true model', which is probably not the case.<o:p></o:p> <h5 style="text-align:justify;tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt">- Copy of the parameter file: <a href="orbiaspar.txt">orbiaspar.txt<o:p></o:p></a></h5> This copy of the parameter file can be useful to re-run the program while saving the old output files. <o:p></o:p> <h5 style="text-align:justify;tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt">- Prevalence forecasting: <a href="frbiaspar.txt">frbiaspar.txt<o:p></o:p></a></h5> First, we have estimated the observed prevalence between 1/1/1984 and 1/6/1988.  The mean date of interview (weighed average of the interviews performed between1/1/1984 and 1/6/1988) is estimated to be 13/9/1985, as written on the top on the file. Then we forecast the probability to be in each state. <o:p></o:p> Example, at date 1/1/1989 : <o:p></o:p> # StartingAge FinalAge P.1 P.2 P.3<o:p></o:p> # Forecasting at date 1/1/1989 <o:p></o:p> 73 0.807 0.078 0.115 <o:p></o:p> Since the minimum age is 70 on the 13/9/1985, the youngest forecasted age is 73. This means that at age a person aged 70 at 13/9/1989 has a probability to enter state1 of 0.807 at age 73 on 1/1/1989. Similarly, the probability to be in state 2 is 0.078 and the probability to die is 0.115. Then, on the 1/1/1989, the prevalence of disability at age 73 is estimated to be 0.088.<o:p></o:p> <h5 style="text-align:justify;tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt">- Population forecasting: <a href="poprbiaspar.txt">poprbiaspar.txt<o:p></o:p></a></h5> <pre style="text-align:justify"># Age P.1 P.2 P.3 [Population]<o:p></o:p></pre> <pre style="text-align:justify"># Forecasting at date 1/1/1989 <o:p></o:p></pre> <pre style="text-align:justify">75 572685.22 83798.08 <o:p></o:p></pre> <pre style="text-align:justify">74 621296.51 79767.99 <o:p></o:p></pre> <pre style="text-align:justify">73 645857.70 69320.60 <o:p></o:p></pre> <pre style="text-align:justify"># Forecasting at date 1/1/1990<o:p></o:p></pre> <pre style="text-align:justify">76 442986.68 92721.14 120775.48</pre> <pre style="text-align:justify">75 487781.02 91367.97 121915.51</pre> <pre style="text-align:justify">74 512892.07 85003.47 117282.76 </pre> <pre style="text-align:justify"> <o:p></o:p></pre> From the population file, we estimate the number of people in each state. At age 73, 645857 persons are in state 1 and 69320 are in state 2. One year latter, 512892 are still in state 1, 85003 are in state 2 and 117282 died before 1/1/1990.<o:p></o:p> <pre style="text-align:justify"> <o:p></o:p></pre> <hr> <h2 style="text-align:justify;tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><a name="example"></a>Trying an example<o:p></o:p></h2> Since you know how to run the program, it is time to test it on your own computer. Try for example on a parameter file named <a href="..\mytry\imachpar.txt">imachpar.txt</a> which is a copy of mypar.txt included in the subdirectory of imach, mytry. Edit it to change the name of the data file to ..\data\mydata.txt if you don't want to copy it on the same directory. The file mydata.txt is a smaller file of 3,000 people but still with 4 waves. <o:p></o:p> Click on the imach.exe icon to open a window. Answer to the question: 'Enter the parameter file name:'<o:p></o:p> <table border="1" cellpadding="0" style="mso-cellspacing:1.5pt;mso-padding-alt: 0cm 0cm 0cm 0cm"> <tr> <td width="100%" style="width:100.0%;padding:.75pt .75pt .75pt .75pt">IMACH, Version 0.7<o:p></o:p>Enter the parameter file name: ..\mytry\imachpar.txt<o:p></o:p> </td> </tr> </table> Most of the data files or image files generated, will use the 'imachpar' string into their name. The running time is about 2-3 minutes on a Pentium III. If the execution worked correctly, the outputs files are created in the current directory, and should be the same as the mypar files initially included in the directory mytry.<o:p></o:p> <pre style="margin-left:36.0pt;text-indent:-18.0pt;mso-list:l5 level1 lfo43">�                Output on the screen The output screen looks like <a href="imachrun.LOG">this Log file<o:p></o:p></a></pre> <pre style="margin-left:18.0pt"> <o:p></o:p></pre> <pre style="margin-left:18.0pt">#title=MLE datafile=..\data\mydata.txt lastobs=3000 firstpass=1 lastpass=3<o:p></o:p></pre> <pre style="margin-left:18.0pt">ftol=1.000000e-008 stepm=24 ncov=2 nlstate=2 ndeath=1 maxwav=4 mle=1 weight=0<o:p></o:p></pre> <pre style="margin-left:18.0pt">Total number of individuals= 2965, Agemin = 70.00, Agemax= 100.92<o:p></o:p></pre> <pre style="margin-left:18.0pt"> <o:p></o:p></pre> <pre style="margin-left:18.0pt">Warning, no any valid information for:126 line=126<o:p></o:p></pre> <pre style="margin-left:18.0pt">Warning, no any valid information for:2307 line=2307<o:p></o:p></pre> <pre style="margin-left:18.0pt;text-align:justify">Delay (in months) between two waves Min=21 Max=51 Mean=24.495826<o:p></o:p></pre> <pre style="margin-left:18.0pt;text-align:justify">These lines give some warnings on the data file and also some raw statistics on frequencies of transitions.<o:p></o:p></pre> <pre style="margin-left:18.0pt;text-align:justify">Age 70 1.=230 loss[1]=3.5% 2.=16 loss[2]=12.5% 1.=222 prev[1]=94.1% 2.=14<o:p></o:p></pre> <pre style="margin-left:18.0pt;text-align:justify"> prev[2]=5.9% 1-1=8 11=200 12=7 13=15 2-1=2 21=6 22=7 23=1<o:p></o:p></pre> <pre style="margin-left:18.0pt;text-align:justify">Age 102 1.=0 loss[1]=NaNQ% 2.=0 loss[2]=NaNQ% 1.=0 prev[1]=NaNQ% 2.=0 <o:p></o:p></pre> <ul type="disc"> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l6 level1 lfo46;tab-stops:list 36.0pt">Maximisation with the Powell algorithm. 8 directions are given corresponding to the 8 parameters. This can be rather long to get convergence. Powell iter=1 -2*LL=11531.405658264877 1 0.000000000000 2 0.000000000000 3 0.000000000000 4 0.000000000000 5 0.000000000000 6 0.000000000000 7 0.000000000000 8 0.000000000000 1..........2.................3..........4.................5......... 6................7........8............... Powell iter=23 -2*LL=6744.954108371555 1 -12.967632334283 2 0.135136681033 3 -7.402109728262 4 0.067844593326 5 -0.673601538129 6 -0.006615504377 7 -5.051341616718 8 0.051272038506 1..............2...........3..............4........... 5..........6................7...........8......... #Number of iterations = 23, -2 Log likelihood = 6744.954042573691 # Parameters 12 -12.966061 0.135117 13 -7.401109 0.067831 21 -0.672648 -0.006627 23 -5.051297 0.051271 <o:p></o:p></li> </ul> <pre style="margin-left:36.0pt;text-align:justify;text-indent:-18.0pt; mso-list:l6 level1 lfo46">�                Calculation of the hessian matrix. Wait...<o:p></o:p></pre> <pre style="margin-left:18.0pt;text-align:justify">12345678.12.13.14.15.16.17.18.23.24.25.26.27.28.34.35.36.37.38.45.46.47.48.56.57.58.67.68.78<o:p></o:p></pre> <pre style="margin-left:18.0pt;text-align:justify"> <o:p></o:p></pre> <pre style="margin-left:18.0pt;text-align:justify">Inverting the hessian to get the covariance matrix. Wait...</pre> <pre style="margin-left:18.0pt;text-align:justify"> <o:p></o:p></pre> <pre style="margin-left:18.0pt;text-align:justify">#Hessian matrix#</pre> <pre style="margin-left:18.0pt">3.344e+002 2.708e+004 -4.586e+001 -3.806e+003 -1.577e+000 -1.313e+002 3.914e-001 3.166e+001 <o:p></o:p></pre> <pre style="margin-left:18.0pt">2.708e+004 2.204e+006 -3.805e+003 -3.174e+005 -1.303e+002 -1.091e+004 2.967e+001 2.399e+003 <o:p></o:p></pre> <pre style="margin-left:18.0pt">-4.586e+001 -3.805e+003 4.044e+002 3.197e+004 2.431e-002 1.995e+000 1.783e-001 1.486e+001 <o:p></o:p></pre> <pre style="margin-left:18.0pt">-3.806e+003 -3.174e+005 3.197e+004 2.541e+006 2.436e+000 2.051e+002 1.483e+001 1.244e+003 <o:p></o:p></pre> <pre style="margin-left:18.0pt">-1.577e+000 -1.303e+002 2.431e-002 2.436e+000 1.093e+002 8.979e+003 -3.402e+001 -2.843e+003 <o:p></o:p></pre> <pre style="margin-left:18.0pt">-1.313e+002 -1.091e+004 1.995e+000 2.051e+002 8.979e+003 7.420e+005 -2.842e+003 -2.388e+005 <o:p></o:p></pre> <pre style="margin-left:18.0pt">3.914e-001 2.967e+001 1.783e-001 1.483e+001 -3.402e+001 -2.842e+003 1.494e+002 1.251e+004 <o:p></o:p></pre> <pre style="margin-left:18.0pt">3.166e+001 2.399e+003 1.486e+001 1.244e+003 -2.843e+003 -2.388e+005 1.251e+004 1.053e+006 <o:p></o:p></pre> <pre style="margin-left:18.0pt;text-align:justify"># Scales<o:p></o:p></pre> <pre style="margin-left:18.0pt;text-align: justify">12 1.00000e-004 1.00000e-006<o:p></o:p></pre> <pre style="margin-left:18.0pt;text-align:justify">13 1.00000e-004 1.00000e-006<o:p></o:p></pre> <pre style="margin-left: 18.0pt;text-align:justify">21 1.00000e-003 1.00000e-005<o:p></o:p></pre> <pre style="margin-left:18.0pt;text-align:justify">23 1.00000e-004 1.00000e-005<o:p></o:p></pre> <pre style="margin-left: 18.0pt;text-align:justify"># Covariance<o:p></o:p></pre> <pre style="margin-left:18.0pt;text-align:justify">  1 5.90661e-001<o:p></o:p></pre> <pre style="margin-left:18.0pt;text-align:justify">  2 -7.26732e-003 8.98810e-005<o:p></o:p></pre> <pre style="margin-left:18.0pt;text-align:justify">  3 8.80177e-002 -1.12706e-003 5.15824e-001<o:p></o:p></pre> <pre style="margin-left:18.0pt;text-align:justify">  4 -1.13082e-003 1.45267e-005 -6.50070e-003 8.23270e-005<o:p></o:p></pre> <pre style="margin-left:18.0pt;text-align:justify">  5 9.31265e-003 -1.16106e-004 6.00210e-004 -8.04151e-006 1.75753e+000<o:p></o:p></pre> <pre style="margin-left:18.0pt;text-align:justify">  6 -1.15664e-004 1.44850e-006 -7.79995e-006 1.04770e-007 -2.12929e-002 2.59422e-004<o:p></o:p></pre> <pre style="margin-left:18.0pt;text-align:justify">  7 1.35103e-003 -1.75392e-005 -6.38237e-004 7.85424e-006 4.02601e-001 -4.86776e-003 1.32682e+000<o:p></o:p></pre> <pre style="margin-left:18.0pt;text-align:justify">  8 -1.82421e-005 2.35811e-007 7.75503e-006 -9.58687e-008 -4.86589e-003 5.91641e-005 -1.57767e-002 1.88622e-004<o:p></o:p></pre> <pre style="margin-left:18.0pt;text-align:justify"># agemin agemax for lifexpectancy, bage fage (if mle==0 ie no data nor Max likelihood).<o:p></o:p></pre> <pre style="margin-left:18.0pt;text-align:justify"> <o:p></o:p></pre> <pre style="margin-left:18.0pt;text-align:justify"> <o:p></o:p></pre> <pre style="margin-left:18.0pt;text-align:justify">agemin=70 agemax=100 bage=50 fage=100<o:p></o:p></pre> <pre style="margin-left:18.0pt;text-align:justify">Computing prevalence limit: result on file 'plrmypar.txt' <o:p></o:p></pre> <pre style="margin-left:18.0pt;text-align:justify">Computing pij: result on file 'pijrmypar.txt' <o:p></o:p></pre> <pre style="margin-left:18.0pt;text-align:justify">Computing Health Expectancies: result on file 'ermypar.txt' <o:p></o:p></pre> <pre style="margin-left:18.0pt;text-align:justify">Computing Variance-covariance of DFLEs: file 'vrmypar.txt' <o:p></o:p></pre> <pre style="margin-left:18.0pt;text-align:justify">Computing Total LEs with variances: file 'trmypar.txt' <o:p></o:p></pre> <pre style="margin-left:18.0pt;text-align:justify">Computing Variance-covariance of Prevalence limit: file 'vplrmypar.txt' <o:p></o:p></pre> <pre style="margin-left:18.0pt;text-align:justify">End of Imach<o:p></o:p></pre> Once the running is finished, the program requires a caracter:<o:p></o:p> <table border="1" cellpadding="0" style="mso-cellspacing:1.5pt;mso-padding-alt: 0cm 0cm 0cm 0cm"> <tr> <td width="100%" style="width:100.0%;padding:.75pt .75pt .75pt .75pt">Type e to edit output files, c to start again, and q for exiting:<o:p></o:p></td> </tr> </table> First you should enter e to edit the master file mypar.htm. <o:p></o:p> <ul type="disc"> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l9 level1 lfo49;tab-stops:list 36.0pt">Outputs files - Observed prevalence in each state: <a href="..\mytry\prmypar.txt">pmypar.txt</a> - Estimated parameters and the covariance matrix: <a href="..\mytry\rmypar.txt">rmypar.txt</a> - Stationary prevalence in each state: <a href="..\mytry\plrmypar.txt">plrmypar.txt</a> - Transition probabilities: <a href="..\mytry\pijrmypar.txt">pijrmypar.txt</a> - Copy of the parameter file: <a href="..\mytry\ormypar.txt">ormypar.txt</a> - Life expectancies by age and initial health status: <a href="..\mytry\ermypar.txt">ermypar.txt</a> - Variances of life expectancies by age and initial health status: <a href="..\mytry\vrmypar.txt">vrmypar.txt</a> - Health expectancies with their variances: <a href="..\mytry\trmypar.txt">trmypar.txt</a> - Standard deviation of stationary prevalence: <a href="..\mytry\vplrmypar.txt">vplrmypar.txt</a> - Prevalences forecasting: <a href="frmypar.txt">frmypar.txt</a> - Population forecasting (if popforecast=1): <a href="poprmypar.txt">poprmypar.txt</a> <o:p></o:p></li> <li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l9 level1 lfo49;tab-stops:list 36.0pt">Graphs -<a href="..\mytry\pemypar1.gif">One-step transition probabilities</a> -<a href="..\mytry\pmypar11.gif">Convergence to the stationary prevalence</a> -<a href="..\mytry\vmypar11.gif">Observed and stationary prevalence in state (1) with the confident interval</a> -<a href="..\mytry\vmypar21.gif">Observed and stationary prevalence in state (2) with the confident interval</a> -<a href="..\mytry\expmypar11.gif">Health life expectancies by age and initial health state (1)</a> -<a href="..\mytry\expmypar21.gif">Health life expectancies by age and initial health state (2)</a> -<a href="..\mytry\emypar1.gif">Total life expectancy by age and health expectancies in states (1) and (2).</a> <o:p></o:p></li> </ul> This software have been partly granted by <a href="http://euroreves.ined.fr">Euro-REVES</a>, a concerted action from the European Union. It will be copyrighted identically to a GNU software product, i.e. program and software can be distributed freely for non commercial use. Sources are not widely distributed today. You can get them by asking us with a simple justification (name, email, institute) <a href="mailto:brouard@ined.fr">mailto:brouard@ined.fr</a> and <a href="mailto:lievre@ined.fr">mailto:lievre@ined.fr</a> .<o:p></o:p> Latest version (0.7 of February 2002) can be accessed at <a href="http://euroreves.ined.fr/imach">http://euroreves.ined.fr/imach<o:p></o:p></a> </body> </html>