04: Hypothesis Testing

Using R to follow the “steps” of hypothesis testing

These are all of the instructions for Lab 4. The list of labs is here.

This repository contains R labs for R package ({psychRstats}) based on Bard College’s Statistics for Psychology (PSY 203, Fall 2020), taught by Assistant Professor of Psychology Justin Dainer-Best.

For each lab, you should expect to download the lab’s files locally to your computer, and run them there. If you’re using https://rstudio.cloud/ instead of running things locally, the same instructions should work today.

Find the full list of labs here.

Below are instructions for Lab 4.

Today’s tutorial

The following lab explores the ideas of hypothesis-testing as explored in the initial classes, using examples from z-scores to continue experimenting with visualizations and continue exploring real data. You should have completed the initial three labs, have a base-level understanding of the goals and procedures of hypothesis-testing, and be ready to practice using R.

To run the tutorial:

library(psychRstats)
psychRstats::lab("04-test-hypotheses")

Once you’ve completed the tutorial, return here for the exercise that you will turn in at the end of the lab. (If you’d like to keep the tutorial open, refer to this page on the wiki.)

Make sure you’re in the right working directory

In the first lab, we set the working directory to a specific folder where every lab for this class will live. If you don’t remember, look at the wiki page I’ve created on setting a working directory.

Check that you’re in the directory you expect by running getwd() (the parentheses should have nothing in them).

Exercise

This exercise explores the commands you learned and lets you continue practicing the steps of hypothesis testing.

You should have downloaded the exercise and data already; today’s file is called “04-exercise.Rmd”. Either open the file (in R through the Files pane, or by double-clicking on the file in your file browser), or you may be able to open the file from the correct working directory by running the following code:

library(psychRstats)
run_exercise("04-exercise")

Solutions

A version of the document with solutions can be seen here.