The Analytics Edge

1.3 Working with Data: An Introduction to R

Quick Question

If you want to know the mean value of a numerical variable, which function could you use?

str close

  

summary check

  

I can’t figure out this information using either of these functions. close

  

Check   Show Solution

Explanation If you using the summary function (in the video, we typed summary(WHO) in our R console) you can see a statistical summary of each variable. For numerical variables, the mean value is listed.

If you want to know the standard deviation of a numerical variable, which function could you use?

str close

  

summary close

  

I can’t figure out this information using either of these functions. check

  

Check   Show Solution

Explanation Neither the str function nor the summary function provides the standard deviation value of a variable. We'll see how to compute this value in the next video.

• Back: Video 4: Loading Data Files
• Continue: Video 5: Data Analysis - Summary Statistics and Scatterplots