Please answer these questions:

1-As the confidence level increases, what happens to the width of the confidence interval?

-It gets narrower

-There isn't enough information to tell.

-It stays the same width

-It gets wider.

2-If we use a larger sample size, what happens to the width of the confidence interval?

-It stays the same width.

-There isn't enough information to tell.

I-t gets narrower.

-It gets wider.

3-What would you need to change in a study to cut the margin of error in half?

Explain:

4-If our sample data are less variable (more minor sample standard deviation, s), what happens to the width of the confidence interval?

-It gets narrower.

-There isn't enough information to tell.

-It stays the same width.

-It gets wider.

5-In the Night Lights and Nearsightedness study, what are the observational units?

-The children

-The night lights

-The parents

6- here are two variables to consider in the Night Lights and Nearsightedness study, identify and classify both of the variables.

-Variable 1: Whether the child slept with a room light, a night light or in darkness (categorical)

-Variable 2: Whether or not the child was nearsighted. (categorical)

-Variable 1: Whether the child slept with a room light, a night light or in darkness (quantitative)

Variable 2: Whether or not the child was nearsighted. (quantitative)

-Variable 1: The percentage of children that slept with a nightlight (quantitative)

Variable 2: The percentage of children that were nearsighted. (quantitative)

7-Identify each of the variables in the study as an explanatory variable or a response variable.

-Explanatory: Whether the child slept with the room light, a night light, or in darkness.

Response: Whether or not the child was nearsighted.

-Explanatory: Whether or not the child was nearsighted.

Response: Whether the child slept with the room light, a night light, or in darkness.

-Explanatory: The percentage of children that slept with a nightlight

Response: The percentage of children that were nearsighted.

-Explanatory: The percentage of children that were nearsighted.

Response: The percentage of children that slept with a nightlight.

8-Although it is possible that the lighting conditions directly impacted the children's eye conditions, identify at least two alternative explanations for the children's nearsightedness.

Explanation:

9-Imagine that you are planning a study to look for an association between overall health (good, fair, not good) and having a pet.

Which variable would be explanatory, and which would be the response?

-Explanatory: The overall health of the person.

Response: Whether or not the person has a pet.

-Explanatory: Whether or not the person has a pet.

Response: The overall health of the person.