Chapter 12, Problem 79BITH

The percent of female wage and salary workers who are paid hourly rates is given in Table 12.30 for the years 1979

to 1992.

Year	Percent of workers paid hourly rates
1979	61.2
1980	60.7
1981	61.3
1982	61.3
1983	61.8
1984	61.7
1985	61.8
1986	62
1987	62.7
1990	62.8
1992	62.9

Table 12.30

a. Using “year” as the independent variable and “percent” as the dependent variable, draw a scatter plot of the data.

b. Does it appear from inspection that there is a relationship between the variables? Why or why not?

c. Calculate the least-squares line. Put the equation in the form of: y = a + bx

d. Find the correlation coefficient. Is it significant?

e. Find the estimated percents for 1991 and 1988.

f. 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?

g. Are there any outliers in the data?

h. What is the estimated percent for the year 2050? Does the least-squares line give an accurate estimate for that

year? Explain why or why not.

i. What is the slope of the least-squares (best-fit) line? Interpret the slope.