Chapter 12.1, Problem 28E

To determine

To find: the correct option of the following would have resulted in a violation of the conditions for the inference.

Answer to Problem 28E

If the entire sample was selected from one classroom

Explanation of Solution

Given:

  

Conditions for the regression inference: Linear, Equal standard deviation Independent, Normal and Random.

1. Violation, the reason is that the sample requires being a random sample.
2. No violation, the reason is that there is no condition on the sample size.
3. No violation, the reason is that there requires to be about a linear relationship (Linear condition) between x and y. but not required a perfect line relationship.
4. No violation, there is no condition on distribution of the y-variable.
5. No violation, the reason is that the Equal standard deviation condition needs that the vertical spread of the residuals In the residual figure is the same everywhere (which therefore refers to the standard deviation of the residuals and not to the standard deviation of x or y variables).

Hence, the correct option is (a)