Stata Press is pleased to announce the release of An Introduction to Stata for Health Researchers, Fifth Edition, by Svend Juul and Morten Frydenberg. This book debuted at #1 on Kindle’s new release list for Probability & Statistics and debuted on the top ten list on Kindle’s new release list for Mathematics. Read more…
Categories: New Books, New Products, Resources Tags: 5th, biostatistics, books, data management, datasets, epidemiology, fifth edition, forthcoming, Frydenberg, health policy, health research, health researchers, ICD-10, ICD-9, introduction, Juul, Morton, power, precision, public health, sample-size analysis, Stata 17, stata press, Svend, tables, textbook, unicode
Stata Press is pleased to announce the release of Data Management Using Stata: A Practical Handbook, Second Edition by Michael N. Mitchell.
Whether you are a new user needing to import, clean, and prepare data for your first analysis in Stata or you are an experienced user hoping to learn new tricks for the most challenging tasks, this book is for you. You can jump straight to the section of the book that discusses the particular challenge you are facing. There you will find a clear explanation of how to approach the problem and illustrative examples to guide you. Read more…
Categories: New Books, Resources, Stata Products Tags: books, data management, forthcoming, handbook, michael mitchell, mitchell, release, reproducibility, Stata 16, stata press, unicode
Data management and data cleaning are critically important steps in any data analysis. Many of us learned this lesson the hard way. Have you ever fit a model that includes age as a covariate and forgotten to convert the missing value codes of -99 to missing values? I have. Or maybe you overlooked a data entry error that resulted in an age of 354 that should have been 54. I’ve done that too. Careful data management and cleaning can help us avoid these kinds of embarrassing mistakes.
I recently recorded a series of data management videos for the Stata Youtube Channel. You can click on the links below to watch the videos. I included topics that I think are important, but the list is far from exhaustive. If you would like to see videos on additional topics, please leave your suggestion in the comments below.
Data management playlist
You can learn more about these topics and many others in the Data Management Reference Manual.
Time-series data, such as financial data, often have known gaps because there are no observations on days such as weekends or holidays. Using regular Stata datetime formats with time-series data that have gaps can result in misleading analysis. Rather than treating these gaps as missing values, we should adjust our calculations appropriately. I illustrate a convenient way to work with irregularly spaced dates by using Stata’s business calendars.
In nasdaq.dta, I have daily data on Read more…
Converting a string date
Stata has a wide array of tools to work with dates. You can have dates in years, months, or even milliseconds. In this post, I will provide a brief tour of working with dates that will help you get started using all of Stata’s tools.
When you load a dataset, you will notice that every variable has a display format. For date variables, the display format is %td for daily dates, %tm for monthly dates, etc. Let’s load the wpi1 dataset as Read more…