# Scatter Plot, Trendline Equation, Correlation and Regression

1. Make an Excel scatter plot. What does it suggest about the population correlation between X and Y?

Part-Time Weekly Earnings ($) by College Students

Hours Worked (X) Weekly Pay (Y)

10 93

15 171

20 204

20 156

35 261

2. Make an Excel scatter plot. What does it suggest about the population correlation between X and Y? (Add the equation to the chart)

Data Set Telephone Hold Time (min.) for Concert Tickets

Operators (X) Wait Time (Y)

4 385

5 335

6 383

7 344

8 288

3. Interpret the slope of the fitted regression HomePrice = 125,000 + 150 SquareFeet. (b) What

is the prediction for HomePrice if SquareFeet = 2,000? (c) Would the intercept be meaningful if

this regression applies to home sales in a certain subdivision?

4. Choose one of these three data sets. (a) Make a scatter plot. (b) Let Excel estimate the regression line, with fitted equation and R2. (c) Describe the fit of the regression.

Commercial Real Estate (X = assessed value, $000; Y = floor space, sq. ft.)

Assessed Size

1,796 4,790

1,544 4,720

2,094 5,940

1,968 5,720

1,567 3,660

1,878 5,000

949 2,990

910 2,610

1,774 5,650

1,187 3,570

1,113 2,930

671 1,280

1,678 4,880

710 1,620

678 1,820

https://brainmass.com/statistics/statistical-figures/295640