An Elementary School Principal Wants to Know the Mean Number

question 22

Multiple Choice

An elementary school principal wants to know the mean number of children in families whose children attend this school. He checks all the families using the school's registration records, and we use the computer to create a 95% confidence interval based on a t-distribution. This procedure was not appropriate. Why?

• A) The recent record-setting family with twelve children is probably an outlier.
• B) The entire population of families was gathered so there is no reason to do inference.
• C) At a given school families are not randomly selected.
• D) Since these families are from only one school, the family sizes may be skewed.
• E) The population standard deviation is known, so he should have used a z-model.

---

Definitions:

Physiological State

The condition of normal function or activity of the body and its systems, often influenced by factors like health, genetics, and environment.

Drive

An aroused state that occurs because of a physiological need.

Optimum Arousal Theory

The theory that individuals perform best and are most productive at a moderate level of arousal, rather than at lower or higher levels.

Moderate Arousal

An optimal level of alertness or activation that enhances performance on tasks or activities, according to Yerkes-Dodson Law.