This looks really promising. I'm definitely going to keep this in mind if the opportunity comes up for me to teach stats. [Read more…]

# #rstats

## How to get graphs publication ready

Note that jtools package has plotting capabilities for interactions that include a continuous variable, and categorical x categorical interactions.

## Installing R packages when corporate firewalls get in the way

So, apparently the antivirus software on my work computer (which I have no control over) is equipped with "real time file system protection." I don't really know what that is, but I know that it often prevents me from installing R packages on my machine, which in turn makes it very difficult to get my analysis done. I don't know how many people have the same problem, but I'm posting it here for my reference.

## Importing a raw Qualtrics file into R

The challenge with Qualtrics is that the files tend to have two top rows: variable names and variable descriptions. This is not a handy format for future data manipulation. Here is the code that I use to import the data without that row of descriptions.

## Transforming variables in R (with dplyr)

### Centering and scaling predictors

This seems to be no longer necessary, now that jtools has a function called "summ" that allows you to get different output than the old-school "summary" call. These outputs include centering or scaling predictors, confidence intervals, and robust standard errors.

## Bringing in Qualtrics (and other data)

Check out my R Club post: Bringing in Qualtrics (and other data)

## Manipulating Qualtrics Data in R

I've decided to automate one of the most tedious processes that we do here.

This R code combines data from our Qualtrics studies with demographics. Basically, it removes duplicate demos, eliminates students without student ID, ie, "test", merges the two datasets, then outputs the data as a CSV file so that you can work with it in Excel or SPSS. The required inputs are the names of the two files (demos and study data) and the directory they are stored in. It outputs the combined file to the same directory.

## Follow up to my p-curve post

Yates's or no Yates's? Pearson's chi-squared versus Fisher's Exact test? I look at the chi-squared test from a previous post and attempt to discover which method is the best at determining independence of two groups.

## Predictive modeling in R

I am presenting to R Club today on predictive modeling, a subject that I've been really interested in. It was quite a bit of work to prepare for it, but I feel like I got a lot out of it.

## Mapping with GGPLOT2 in R

In R Club, we worked on making maps. Here is mine: [Read more…]

## P Curve Analytic Thinking

A few weeks ago we spoke with Joe Simmons from Wharton about his P-curve methodology of reviewing papers. A p-curve is a graph of all of the p-values in a paper. When you graph all of the significant p-values, you want them to all bunch up close to zero. [Read more…]

## Intro to R Programming for Marketing Researchers

This is for a class I taught…

## Data Wrangling with R

I just added some good information about data wrangling to the R Club blog.