Frailty, Advanced Statistics

Assignment Help:

A term usually used for unobserved individual heterogeneity. Such variation is of main concern in the medical statistics particularly in the analysis of the survival times where hazard functions can be strongly influenced by the selection effects operating in the population. There are several possible sources of this heterogeneity, the most apparent of which is that it reflects the biological differences, so that, for instance, some individuals are born with the weaker heart, or a genetic disposition for cancer. A further prospect is that the heterogeneity happens from the occured weaknesses which result from the stresses of life. Failure to take account of this kind of variation might often obscure comparisons between groups, for instance, by measures of relative risk. A simple model which attempts to permit for the variation between individuals is given as follows


1270_fraility.png 


where Z is the quantity specific to an individual, considered as the random variable over the population of individuals, and the base rate is denoted by λ(t) . What is observed in a population for which this type of model holds is not the individual hazard rate but the net result for several individuals with different values of Z.

 


Related Discussions:- Frailty

Poisson regression, Poisson regression In case of Poisson regression w...

Poisson regression In case of Poisson regression we use ηi = g(µi) = log(µi) and a variance V ar(Yi) = φµi. The case φ = 1 corresponds to standard Poisson model. Poisson regre

Computer-aided diagnosis, Computer-aided diagnosis : The computer programs ...

Computer-aided diagnosis : The computer programs which are designed to support clinical decision making. In common, such systems are based on the repeated application of the Bay

Dot plot, The more effective display than a number of other methods or tech...

The more effective display than a number of other methods or techniques, for instance, pie charts and bar charts, for displaying the quantitative data which are labeled. An instanc

Random allocation, Random allocation is a technique for creating the treat...

Random allocation is a technique for creating the treatment and control groups particularly in accordance of the clinical trial. Subjects receive the active treatment or the place

Interior analysis, Interior analysis is the  term now and again applied to...

Interior analysis is the  term now and again applied to analysis carried out on the fitted model in regression problem. The basic target of such analyses is the identification of

Chebyshev''s inequality, Chebyshev's inequality: A statement about the pro...

Chebyshev's inequality: A statement about the proportion of the observations which fall within some number of the standard deviations of the mean for any of the probability distri

LASPEYERES QUANTITY INDEX, HOW TO OBTAIN THE LASPEYRES QUANTITY INDEX AND T...

HOW TO OBTAIN THE LASPEYRES QUANTITY INDEX AND THE FORMULA

Regression analysis, The regression analysis is used to fit a model descr...

The regression analysis is used to fit a model describing the relationship of a dependent variable with independent variable(s). Here we have fitted three regression models:

Find the expected value of perfect information, You may have the opportunit...

You may have the opportunity to buy some electronic components. These components may be reliable (1) or unreliable (2). The potential pro?ts are £10,000 if the components are rel

Daycare, facts and statistics about daycare

facts and statistics about daycare

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd