The percent of women who are wage and salary workers who are paid hourly rates is given in the table for a 14-year period.
| Year | Percent of workers paid hourly rates |
| 1 | 61.2 |
| 2 | 60.7 |
| 3 | 61.3 |
| 4 | 61.3 |
| 5 | 61.8 |
| 6 | 61.7 |
| 7 | 61.8 |
| 8 | 62.0 |
| 9 | 62.7 |
| 12 | 62.8 |
| 14 | 62.9 |
- Using “year” as the independent variable and “percent” as the dependent variable, draw a scatter plot of the data.
- Does it appear from inspection that there is a relationship between the variables? Why or why not?
- Calculate the least-squares line. Put the equation in the form of: ŷ = a + bx
- Find the correlation coefficient. Is it significant?
- Find the estimated percents for year 13 and year 10.
- Based on the data, is there a linear relationship between the year and the percent of female wage and salary earners who are paid hourly rates?
- Are there any outliers in the data?
- What is the estimated percent for the year 72? Does the least-squares line give an accurate estimate for that year? Explain why or why not.
- What is the slope of the least-squares (best-fit) line? Interpret the slope.
OpenStax Introductory Statistics 2e, 12.6 Outliers, exercise 20