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Chapter 13: Problem 67

Will you expect a positive, zero, or negative linear correlation between the two variables for each of the following examples? a. SAT scores and GPAs of students b. Stress level and blood pressure of individuals c. Amount of fertilizer used and yield of corn per acre d. Ages and prices of houses e. Heights of husbands and incomes of their wives

Short Answer

Expert verified
a. Positive correlation\nb. Positive correlation\nc. Positive correlation\nd. Negative correlation\ne. Zero correlation

Step by step solution

01

Identifying Correlation for SAT scores and GPAs of students

SAT scores and GPAs both represent academic performance of students. It can be reasonably expected that a student performing well in school would also perform well on an SAT test. Therefore, a positive correlation is expected.
02

Identifying Correlation for Stress level and blood pressure of individuals

Stress level can affect a person's physical health, including blood pressure. Greater stress levels are often associated with higher blood pressure. Thus, a positive correlation is expected.
03

Identifying Correlation for Amount of fertilizer used and yield of corn per acre

Fertilizer is used to increase the yield of plants. Thus, it can be expected that using more fertilizer will lead to increased corn production. Therefore, a positive correlation is expected.
04

Identifying Correlation for Ages and prices of houses

Typically, as a house ages, its price may decrease due to depreciation, assuming no major renovations or other factors changing it's value. This suggests a negative correlation.
05

Identifying Correlation for Heights of husbands and incomes of their wives

Height of a husband likely has no influence on his wife's income, so there should be no correlation. This suggests a zero correlation.

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