Outliers · Exercise 13

The average number of people in a family that attended college for various years is given in.

$$\begin{array}{cc}\text{Year}& \text{Number of Family Members Attending College}\\ \text{1969}& \text{4.0}\\ \text{1973}& \text{3.6}\\ \text{1975}& \text{3.2}\\ \text{1979}& \text{3.0}\\ \text{1983}& \text{3.0}\\ \text{1988}& \text{3.0}\\ \text{1991}& \text{2.9}\end{array}$$

(a) Using “year” as the independent variable and “Number of Family Members Attending College” as the dependent variable, draw a scatter plot of the data.
(b) Calculate the least-squares line. Put the equation in the form of: ŷ = a + bx
(c) Find the correlation coefficient. Is it significant?
(d) Pick two years between 1969 and 1991 and find the estimated number of family members attending college.
(e) Based on the data in, is there a linear relationship between the year and the average number of family members attending college?
(f) Using the least-squares line, estimate the number of family members attending college for 1960 and 1995. Does the least-squares line give an accurate estimate for those years? Explain why or why not.
(g) Are there any outliers in the data?
(h) What is the estimated average number of family members attending college for 1986? 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.

Its source prints no answer for this problem, so there's nothing to check against.

OpenStax, Introductory Statistics 2e · §12.6 Outliers · Exercise 13