Respondent-driven sampling is a network sampling technique typically employed for hard-to-reach populations (for example, drug users, men who have sex with men, people with HIV). Similarly to snowball sampling, initial seed respondents recruit additional respondents from their network of...

In hierarchical cluster analysis, dendrograms are used to visualize how clusters are formed. I propose an alternative graph called a "clustergram" to examine how cluster members are assigned to clusters as the number of clusters increases. This graph is useful in exploratory analysis for...

Respondent-driven sampling is a network sampling technique typi- cally employed for hard-to-reach populations (for example, drug users, men who have sex with men, people with HIV). Similarly to snowball sampling, initial seed respondents recruit additional respondents from their network of...

Boosting, or boosted regression, is a recent data-mining technique that has shown considerable success in predictive accuracy. This article gives an overview of boosting and introduces a new Stata command, boost, that im- plements the boosting algorithm described in Hastie, Tibshirani, and...