# stratification

1. ### How to obtain an unbiased post-stratified estimator for survival probabilities?

Suppose I have estimated the survival probabilities $\hat{S(t)}_1, \hat{S(t)}_2, \ldots, \hat{S(t)}_H$ from $H$ strata. Now I want to get an unbiased estimate of population survival probability $S(t)$ using these stratum-specific estimates. Then what should be the estimator? Should it be...
2. ### Regression with stratified data: What to do?

Hi, I want to model a bird population in a country via regression analysis (Poisson regression due to count data). In order to optimize the sampling effort versus precision, I use a stratified random design: The country is splitted into 10 different habitats, and from each habitat I draw...
3. ### Linear Regression: Disagreement in confounding with stratification

Hi everyone, I am performing a simple linear regression testing whether an the results from an aptitude test for our sales force is associated with their profitability (binary variable profitable or not). The score variable is a percentile. I performed a simple logistic regression...