Stata version 9 includes the new command xtmixed, for fitting linear mixed models. Mixed models contain both fixed and random effects. The fixed effects are analagous to standard regression coefficients and are estimated directly. The random effects are not directly estimated but are summarized...

The presentation illustrates the user-written program hds97, which implements the restricted least squares procedure as described by Haisken-DeNew and Schmidt (1997). Log wages are regressed on a group of k-1 industry/region/job/etc. dummies. The kth dummy is the omitted reference dummy. Using...

Most Stata users make their living producing results in a form accessible to end users. Most of these end users cannot immediately understand Stata logs. However, they can understand tables (in paper, PDF, HTML, spreadsheet, or word processor documents) and plots (produced by using Stata or...

Sequences are ordered lists of elements. A typical example is the sequence of bases in DNA. Other examples are sequences of employment stages during a lifetime or individual party preferences over time. Sequence analysis include techniques to handle, describe, and, most importantly, compare...

We derive the sampling variances of generalized entropy and Atkinson indices when estimated from complex survey data, and we show how they can be calculated straightforwardly by using widely available software. We also show that, when the same approach is used to derive variance formulae for the...

Recently, Bayesian methods such as Markov chain Monte Carlo (MCMC) techniques have found more use in the social sciences, with (Win)BUGS being one of the most widely applied programs for this kind of analysis. Unfortunately, because of the absence of MCMC techniques and any interfaces to WinBUGS...

Within the framework of economic evaluation, health econometricians are interested in constructing a meaningful health index that is consistent with individual or societal preferences. One way to derive such an index is based on the EQ-5D description and valuation of health-related quality of...

Clustering methods are designed for finding groups in data, i.e., for grouping similar objects (variables or observations) into the same cluster and dissimilar objects into separate clusters. Although the main idea is rather simple, carrying out a cluster analysis remains a challenging task. The...

Stata is quite simple to use for smaller ado-packages stored on user web pages. However, when the number of files in a package becomes large and the files need to be updated regularly, this task becomes cumbersome. Package updates could take a long time to complete. Here a method of storing...