Question

Analyzing student work, what was Ramona’s mistake in using the regression equation to predict height based on shoe size? a. She substituted the wrong variable for 8.5 b. She should have added 0.444 and 8.5 c. The value for y should be negative d. The solution of -17.52 should be the shoe size

Answer 1

Ramona's mistake was that she substituted the wrong variable for 8.5. She should have substituted 8.5 for x (shoe size) in the regression equation, but instead she substituted it for y (height). This resulted in an incorrect prediction of height. Option A is answer.

Step-by-step explanation:

The regression equation is in the form y = mx + b, where y is the predicted value, m is the slope, x is the independent variable, and b is the y-intercept. In this case, y is height, x is shoe_size, m is 0.444, and b is -21.29. Therefore, to predict the height based on shoe_size, you should multiply the shoe_size by 0.444 and then add -21.29.

In Ramona's case, she substituted 8.5 for y instead of x. This means that she was trying to solve for shoe_size based on height, which is not possible using the given regression equation. The correct way to solve for shoe_size based on height would be to use the following equation:

shoe_size = (y + 21.29) / 0.444

Therefore, Ramona's mistake was that she substituted the wrong variable for 8.5, and she should have used the correct equation to solve for shoe_size based on height.

Option A is answer.