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

General location model, The model for data containing continuous and catego...

The model for data containing continuous and categorical variables both.The categorical data are summarized by the contingency table and their marginal distribution, 182by the mult

Vital Statistics, meaning,uses,shortcomings and drawbacks of vital statist...

meaning,uses,shortcomings and drawbacks of vital statistics

Genomics, Genomics  is the study of the structure, function and the evoluti...

Genomics  is the study of the structure, function and the evolution of deoxyribonucleic acid (DNA) or ribonucleic acid (RNA) sequences which comprise the genome of living organisms

Arithmetic mean , a sequence of numbers consist of six 6''s seven 7''s eigh...

a sequence of numbers consist of six 6''s seven 7''s eight 8''s nine 9''s ten 10''s what is the arithmetic mean?

Cointegration, Cointegration : The vector of not motionless time sequence i...

Cointegration : The vector of not motionless time sequence is said to be cointegrated if the linear combination of the individual series is stationary. Facilitates suitable testing

Explain lie factor, Lie factor : A measure suggested by Tufte for judging t...

Lie factor : A measure suggested by Tufte for judging the honesty of the graphical presentation of data. Which can be calculated as follows   The values close to one are desir

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

Random success probability, a psychic claims to be able to "feel colors" th...

a psychic claims to be able to "feel colors" there are three pieces of colored paper(red, blue,green) he will place his hand on radomly selected pieces while blindfolded. you perfo

Mardia''s multivariate normality test, Mardia's multivariate normality test...

Mardia's multivariate normality test is a test that a set of the multivariate data arise from the multivariate normal distribution against departures due to the kurtosis. The test

Explain Genstat, Genstat: The basic purpose piece of statistical software ...

Genstat: The basic purpose piece of statistical software for the management and the analysis of data. The package incorporates the wide variety of data handling events and a wi

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