Interesting paper:

Purposeful selection of variables in logistic regression

Zoran Bursac, Heath Gauss, David Keith Williams and David W Hosmer

Original link : https://scfbm.biomedcentral.com/articles/10.1186/1751-0473-3-17

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# Category: Design of Studies

## Purposeful selection of variables in logistic regression

## Epidemiology and Public Health

## Various sample size formulae

## Sample size for paired t-test

## Using Stata to understand INTERACTION

## Multicolinearity

## Sample size for correlation

## Model building , AIC stepwise selection, backward elimination, all-subsets regression

## run lrtest when observations differ

## What are some of the problems with stepwise regression?

A blog -hopefully- with good balance of epidemiology and statistics

Interesting paper:

Purposeful selection of variables in logistic regression

Zoran Bursac, Heath Gauss, David Keith Williams and David W Hosmer

Original link : https://scfbm.biomedcentral.com/articles/10.1186/1751-0473-3-17

The University of Alabama at Birmingham explains Epidemiology and Public Health. It states

“Public Health is a blend of sciences, skills and convictions that is focused on the preservation and improvement of the health of all people through preventive (rather than curative) measures.

Epidemiology is considered a basic science of public health. Epidemiology is: a) a quantitative discipline built on a working knowledge of probability, statistics, and sound research methods; b) a method of causal reasoning based on developing and testing hypotheses pertaining to occurrence and prevention of morbidity and mortality; and c) a tool for public health action to promote and protect the public’s health based on science, causal reasoning, and a dose of practical common sense (1).

The word epidemiology comes from the Greek words epi, meaning “on or upon,” demos, meaning “people,” and logos, meaning “the study of.” Many definitions have been proposed; here are two that capture the underlying principles and the public health spirit of epidemiology:”

Read more here : http://www.soph.uab.edu/epi/academics/studenthandbook/what

when you face the error message in stata while running lrtest :

observations differ: 77 vs. 73

then use , ‘generate sample’, refer here