Gaussian integration can be used to obtain surprisingly accurate evaluations of definite integrals with as few as 10 or 20 function evaluations. In this presentation, it will be shown how to incorporate tables of Gaussian integration weights into Stata data sets and use them to evaluate...

Stata's graphics are more flexible than many realise. We will exploit this flexibility and explore a potpourri of topics, some of interest to all graphers and others primarily of interest to those creating highly customised graphs or new graph commands. Among the topics will be creating custom...

Consider a longitudinal study designed to estimate the difference in the rates of change in some outcome between two different groups. In this case, the variance of the estimator depends on several factors, including the variability in the outcome, the amount of missing data due to dropout, the...

This talk will describe some work underway to add a "rolling regression" capability to Stata's suite of time series features. Although commands such as "statsby" permit analysis of non-overlapping subsamples in the time domain, they are not suited to the analysis of overlapping (e.g. "moving...

One way to evaluate the econometric techniques of estimating treatment effects is to use experimental data to gauge results of different methods (LaLonde 1986 AER). There has been heated debate since LaLonde!'s seminal paper as to whether the propensity score techniques overcome the selection...

As web-based and other electronic data collection methods become more widely used in research, the opportunities to use statistical software in conjunction with conventional database systems are increasing. Among such systems, MySQL is particularly well suited for research purposes. For example,...

While Stata has gained wide acceptance in academia, its use in corporate environments lags far behind. For academic Stata users, the product's inability to penetrate business has important consequences. Students trained in Stata have fewer opportunities than those trained in other tools,...

With its suite of ODBC-related commands, Stata may now be used directly with many popular database management systems (DBMSs) and other ODBC data sources. Stat/Transfer's ODBC capabilities have permitted indirect access for some time. ODBC has advantages over copy-and-paste or save-as/insheet...

Liang and Zeger's original formulation of generalized estimating equations (GEE) has been widely applied since its introduction in 1986 because it extends the application of generalized linear models to clustered data. In this presentation we discuss a method, quasi-least squares (QLS), that is...

Density distribution sunflower plots are used to display high-density bivariate data. They are useful for data where a conventional scatter plot is difficult to read due to overstriking of the plot symbol. The x-y plane is subdivided into a lattice of regular hexagonal bins of width w specified...