Question 1

Which of the following best describes a discrete variable?

Accepted Answer

A variable whose possible values can be listed, such as the number of siblings.

Question 2

Given the following frequency table for IQ scores, what is the class midpoint for the class 90-109?

IQ score: 90-109

$$	ext{Class Midpoint} = \frac{90 + 109}{2}$$

Accepted Answer

$$99.5$$

Question 3

A histogram is constructed for the weights of a group of people. The bars are all approximately the same height. What type of distribution does this histogram represent?

Accepted Answer

Uniform distribution

Question 4

Which of the following is a key advantage of using a relative frequency distribution instead of a frequency distribution?

Accepted Answer

It allows for easier comparison between data sets of different sizes.

Question 5

A histogram of McDonald's lunch service times is shown with a longer tail to the right. Which term best describes the shape of this distribution?

Accepted Answer

Skewed to the right

Question 6

If a frequency table has lower class limits of 3, 5, 7, 9, and 11, and upper class limits of 4.9, 6.9, 8.9, 10.9, and 12.9, what is the class width?

Accepted Answer

Question 7

Which of the following graphs is most appropriate for displaying the relationship between two quantitative variables?

Accepted Answer

Scatterplot

Question 8

A correlation coefficient $$r is $$calculated to be $$-0.85$$ for two variables. Which of the following best describes the relationship?

Accepted Answer

Strong negative linear correlation

Question 9

Which of the following is a potential problem with using pictographs to represent data?

Accepted Answer

They can exaggerate differences by using two- or three-dimensional objects.

Question 10

A cumulative frequency table is constructed for test scores. What does the cumulative frequency for a class represent?

Accepted Answer

The sum of the frequencies for that class and all previous classes.

Question 11

Which of the following statements about the linear correlation coefficient $$r is $$FALSE?

Accepted Answer

It can be greater than 1 or less than -1.

Question 12

A pie chart is used to display the distribution of favorite colors among students. Which of the following is a limitation of using a pie chart?

Accepted Answer

It becomes difficult to read if there are more than 10 categories.

Question 13

Which of the following best describes a bimodal distribution?

Accepted Answer

A distribution with two distinct peaks.

Question 14

In a study examining the effect of room temperature on math test scores, which variable is the explanatory variable?

Accepted Answer

Room temperature

Question 15

Which of the following is NOT a feature of a histogram?

Accepted Answer

Bars are separated by gaps to show different categories.

Question 16

A dataset of arm circumferences is graphed and shows a symmetric, bell-shaped curve. Which distribution does this represent?

Accepted Answer

Normal distribution

Question 17

Which of the following is TRUE about the use of class boundaries in frequency tables?

Accepted Answer

They fill the gaps between class limits to avoid ambiguity.

Question 18

A bar graph is constructed to compare the median income by gender over several decades. What type of bar graph is this?

Accepted Answer

Multiple bar graph

Question 19

Which of the following is a reason why the correlation coefficient $$r$$ does NOT imply causality?

Accepted Answer

It only measures association, not cause and effect.

Question 20

Given a dataset with the following frequencies for red blood cell counts: 2, 7, 15, 13, 3. What is the relative frequency for the class with frequency 15 if the total number of observations is 40?

$$	ext{Relative frequency} = \frac{15}{40}$$

Accepted Answer

$$0.375$$

Exploring Data with Tables and Graphs: Structured Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard