Question

rainfall and corn crop yield reported for the 38 years from 1890 through 1927 give us the scatterplot shown below with an ( r = 0.0426 ). yield is the number of ears of corn measured in metric tons per hectare, rainfall is in inches. based on corn crop yield from ezekiel, m. and k. a. fox. (1959). methods of correlation and regression analysis. wiley: new york. the plot shows a positive linear relationship between the inches of rainfall and the size of the corn yield. which of the following is an appropriate interpretation of the relationship in the data shown above? a. the more rain, the lower the yield of corn. b. the growth rate of corn is positively affected by more rainfall. c. rainfall seems to have a positive effect on the yield of corn.

Explanation:

The scatter - plot shows a positive linear relationship (as indicated by \(r = 0.0426\), a positive correlation coefficient). A positive relationship means that as one variable (rainfall) increases, the other variable (corn yield) also has a tendency to increase.

• Option A is incorrect because it suggests a negative relationship (more rain, lower yield) which is against the positive correlation shown.
• Option B is incorrect as the term "growth rate" is not relevant to the data presented (data is about yield, not growth rate).
• Option C is correct as it aligns with the positive linear relationship (positive effect of rainfall on corn yield) shown in the scatter - plot and the positive correlation coefficient.

Answer:

C. Rainfall seems to have a positive effect on the yield of corn.