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The talk describes recent updates for midas, a comprehensive and medically popular program for diagnostic test accuracy meta-analysis. A major change is that midas is now an estimation command and a wrapper for meglm of Stata 13 . The update allows more flexibility for specifying covariance...
Persistent link: https://www.econbiz.de/10010888643
Good graphics often exploit a simple graphical design repeated for different parts of the data, which Edward R. Tufte dubbed the use of small multiples. In Stata small multiples are supported for different subsets of the data through by() or over() options of many graph commands: users can...
Persistent link: https://www.econbiz.de/10010888644
In this talk, I am demonstrating how a multiple imputation procedure can be built by a user from scratch. The motivating example comes from a public opinion survey in which the sampled respondents were providing their responses on the web or by phone. As is known in survey methodology...
Persistent link: https://www.econbiz.de/10010888645
Solution of nonlinear systems has become increasingly important as a step in many estimation problems, and is a problem of interest in its own right. I introduce a collection of Mata routines that can be used to find all solutions to nonlinear equation systems, and demonstrate their usage on a...
Persistent link: https://www.econbiz.de/10010888646
Data visualization is a burgeoning field at the crossroads of design, computer science, and statistics. Using HTML and applying data visualization techniques allows the creation of elegant and insightful representations with Stata. Nevertheless, creating original "dataviz" from an empty page is...
Persistent link: https://www.econbiz.de/10010933127
Sequence analysis (SA) is a very different way of looking at categorical longitudinal data, such as life-course or labor-market histories (or any ordered categorical data, for that matter). Instead of focusing on transition rates (for example, via hazard rate, Markov or panel models), it takes...
Persistent link: https://www.econbiz.de/10010933759
Researchers do not adequately appreciate that floating-point numbers are a simulation of real numbers and, as with all simulations, some features are preserved while others are not. When writing code, or even do-files, treating the computer's floating-point numbers as if they were real numbers...
Persistent link: https://www.econbiz.de/10010933760
More efficient trial designs are needed to combat the increasing cost of drug development. A class of trial designs that can help to accelerate this process, known as multi-arm multi-stage (MAMS) designs, has been proposed and used to much effect in oncology. To facilitate the design of these...
Persistent link: https://www.econbiz.de/10010933761
The Bayesian approach to statistical analysis has many theoretical advantages, but in the past, its use has been limited by a lack of suitable statistical software. In a book published this year by Stata Press called Bayesian Analysis with Stata, I have tried to show that Stata can be used for...
Persistent link: https://www.econbiz.de/10010933762
The Cox proportional hazards model is one of the most popular methods for analyzing survival or failure-time data. The key assumption underlying the Cox model is that of proportional hazards. This assumption may often be violated in practice. Transformation survival models extend the Cox...
Persistent link: https://www.econbiz.de/10010933763