# Chapter 1. Two-Variable Statistical Calculator

## Introduction

Statistical Applets

Choose a data set on the first tab below, then click the other tabs to view or manipulate the data, see summary statistics including the correlation and equation of the least-squares regression line, or view a scatterplot or residuals plot of the data.

Click the "Quiz Me" button to complete the activity.

Statisticians are often interested in changes in a variable, or relationships among several variables. This applet describes straight-line relationships between two variables using the methods of correlation and regression.

### Question 1.1

Choose "User-entered data" as the dataset, then enter the following pairs of values for Column A (x) and Column B (y):

(7, 10)
(27, 35)
(24, 25)
(8, 12)
(10, 19)
(15, 22)

Enter the following statistics for this dataset (accurate to within 2 decimal places):

• Mean of x: EABNG2fn3flyB0zN
• Mean of y: 7k9v0q5LX0xt2/l8
• Std. dev. of x: kuDnLHDRzr0=
• Std. dev. of y: vcqatSBZW9s=
3
Try again.
Incorrect. See above for the correct answers.
Great job.

### Question 1.2

Now fill in the following values regarding the correlation and regression line for these two variables:

• Slope of regression line: lVex7vblkgI=
• Intercept of regression line: z1DhTws84hA=
• Correlation coefficient: +P4mXX9i4Y0=
3
Try again.
Incorrect. See above for the correct answers.
Great job.