Linear spline (piecewise) models in Stata

I wrote a tutorial on how to construct linear spline (also known as piecewise) models using Stata, which has been uploaded to my RPubs site.

Previously, I have developed tutorial on using the linear spline method for interrupted time series analsyis with Stata. However, I did not properly go over the mkspline commands.

In this tutorial, I review the mkspline command and the marginal option to generate coefficients that could be interpreted as the slope within each segment or the change in slope between segments, respectively.

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Presentations with R Markdown - Part 3: Changing font colors

I continue my series on constructing a presentation using R Markdown with a new addition (Part 3) on font colors. We use colors to highlight text to enhance or draw attention to it. In this article, I provide code on how one can do this in R Markdown’s presentation using revealjs.

Part 3 of this series is available on my RPubs site.

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Survival Analysis - Immortal Time Bias with Stata

I wrote a tutorial on how to handle immortal time bias with survival analysis using Stata. In the tutorial, I used a time-varying predictor for the grouping variable and assigned the period before exposure to the control group. This was inspired by the paper Redelmeier and Singh wrote on “Surival in Academy Award-Winner Actors and Actresses.” There was a lot of debate about the rigor of their analyses, and Sylvestre and colleagues re-analyzed the data with immortal time bias in mind. This tutorial uses data from Sylvestre and colleagues to re-create their results.

The tutorial is on my RPubs page. Data used for the tutorial is located on my GitHub page.

To load the data, you can use the Stata import command

import delimited "https://raw.githubusercontent.com/mbounthavong/Survival-analysis-and-immortal-time-bias/main/Data/data1.csv"

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Building a book using the bookdown package in R - Part 2: Chapters and References

I create a second tutorial on bookdown that provides a high-level overview on how to add chapters and a reference section. It is located on my RPubs site (link).

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I plan on creating more tutorials with the bookdown package, so stay tuned.

Building a book using the bookdown package in R - Part 1

I created a tutorial on building an online book using the R bookdown package. The tutorial is available on my RPubs page, which is located here.

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I plan on creating more tutorials with the bookdown package, so stay tuned.

Building an HTML Presentation using R Markdown - Part 2

This is the second part of a series on how to create HTML presentations using R Markdown.

I posted it on my Rpubs site and my GitHub site.

I plan on writing more tutorials on this subject, so stay tuned.

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Two-part models in R - Application with cost data

I created a tutorial on how to use two-part models in R for cost data. I used the healthcare expenditures from the Medical Expenditure Panel Survey in 2017 as a motivating example. Normally, I use Stata when I construct two-part models. But I wanted to learn how I could do this in R. Fortunately, R has a package called twopartm that was developed by Duan and colleagues. You can find their document for the twopartm package here.

The tutorial I created is located on my GitHub page and RPubs page.

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Building an HTML Presentation Using R Markdown

I learned how to construct an HTML presentation using R Markdown. In order to help myself remember how to do this, I began writing a tutorial. I posted the first part of the tutorial on my RPubs page.

I plan to write more tutorials on this subject, so stay tuned.

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Interpreting regression models

I wrote a short explanation on how to interpret regression models.

I have posted this on RPubs, and the code is saved on my GitHub site.

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MEPS Tutorial - Part 3: Applying survey weights using R

In this tutorial, we will review how survey weights from the Medical Expenditure Panel Survey (MEPS) are applied using R.

The tutorial is available on my GitHub site and RPubs.

The R Markdown code I used to generate this tutorial is available on my GitHub site.

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