Population averaged models, Advanced Statistics

Population averaged models are the models for kind of clustered data in which the marginal expectation of response variable is the main focus of interest. An alternative approach is taken in use to subject-specific models which concentrate on the modelling of the changes in an individual's response.

This is accomplished by the introducing subject-specific random effects into model. The mixed effects model or the multilevel model is an instance. There are two key points which differentiate the two types of model.

* The regression coefficients of the population averaged model define what the average population response looks like. By contrast regression coefficients of a subject-specific model define what the average individual's response curve looks like. In number of the cases and in particular when the model is linear in subject-specific effects, the two interpretations will coincide. In the more usual non-linear setting, though, the two approaches can lead to quite different conclusions.

* A additional distinction lies in specification of the underlying variance-covariance structure. In the population averaged models the marginal expectations are explicitly modelled while choosing the variance-covariance structure which adequately describes the correlation pattern between the repeated measurements. In subject-specific models, yet, individual heterogeneity is modelled using the subject-specific effects and it is these random effects which partially determine variance-covariance structure. c random effects into model. The mixed effects model or the multilevel model is an instance. There are two key points which differentiate the two types of model.

Posted Date: 7/31/2012 1:47:01 AM | Location : United States







Related Discussions:- Population averaged models, Assignment Help, Ask Question on Population averaged models, Get Answer, Expert's Help, Population averaged models Discussions

Write discussion on Population averaged models
Your posts are moderated
Related Questions

You have probably noticed by now that some of the statements of necessary and sufficient conditions sound more natural than others. For example it seems more natural to express "We

The skewness is a measure of asymmetry and as it is positive at 4.29, it is greater than zero which reveals that the tail extends to the right indicating the distribution to be mor

Window estimates is a term which occurs in the context of the both frequency domain and time domain estimation for the time series. In the previous it generally applies to weights

Whats the independent variable in the following sentence? -1) In a drug prevention program for boys and girls, will family-participation result in effective drug use reduction?

Formal graphical representation of the "causal diagrams" or the "path diagrams" where the  relationships are directed but acyclic (that is no feedback relations allowed). Plays an

regression line drawn as Y=C+1075x, when x was 2, and y was 239, given that y intercept was 11. calculate the residual

R-squared is regarded as the coefficient of determination and is used to give the proportion of the fluctuation of the variance of one variable to another variable. R-squared also

Input to the compress is a text le with arbitrary size, but for this assignment we will assume that the data structure of the file fits in the main memory of a computer. Output of

Atomistic fallacy : A fallacy which arises because of the association between two variables at the individual level might vary from the association between the same two variables m