Q: If a data set is perfectly symmetric and unimodal, which of the following is true?

$$\text{Mean} = \text{Median} = \text{Mode}$$

Q: If a distribution is skewed right, which of the following is true?

$$\text{Mean} \u003e \text{Median}$$

Question 1

Which of the following best describes the variable 'make of car' (e.g., Honda, Ford, Toyota) recorded by a researcher from 200 commuters?

Accepted Answer

Qualitative

Question 2

A researcher wants to estimate the average income of all residents in a city. She randomly selects 10 neighborhoods, then surveys every household in those neighborhoods. What sampling method is this?

Accepted Answer

Cluster sampling

Question 3

Which level of measurement is represented by 'calendar year'?

Accepted Answer

Interval

Question 4

A survey of 100 randomly selected students found that 60% prefer online classes. The value 60% is a:

Accepted Answer

Statistic, because 100 students is a sample

Question 5

Which of the following is an example of a continuous variable?

Accepted Answer

Time spent studying

Question 6

A researcher selects every 10th person from a list of conference attendees. What sampling method is this?

Accepted Answer

Systematic sampling

Question 7

Which of the following best describes the distribution shown in the Yelp Ratings for Hot Doug’s graph (first image)?

Accepted Answer

Skewed left

Question 8

Which measure of central tendency is most appropriate for a distribution that is highly skewed by a few extreme values?

Accepted Answer

Median

Question 9

If a data set is perfectly symmetric and unimodal, which of the following is true?

Accepted Answer

$$	ext{Mean} = 	ext{Median} = 	ext{Mode}$$

Question 10

A frequency distribution has a minimum value of 10 and a maximum value of 70. If you want 5 classes, what is the class width?

Accepted Answer

$$\frac{70-10}{5} = 12$$, round up to 13

Question 11

Which of the following is a resistant statistic?

Accepted Answer

Median

Question 12

A researcher wants to study the effect of a new medication. She randomly assigns patients to receive either the medication or a placebo, then measures their blood pressure. What type of study is this?

Accepted Answer

Designed experiment

Question 13

Which of the following best describes the bias present if a survey is only distributed to people who attend a specific event?

Accepted Answer

Sampling bias

Question 14

Given the data set: 5, 7, 8, 12, 15, 20, 100, which measure of central tendency is most affected by the outlier?

Accepted Answer

Mean

Question 15

A survey asks, 'Don’t you agree that our new recycling program is beneficial?' This question is likely to introduce which type of bias?

Accepted Answer

Response bias

Question 16

A data set contains 12 values. Which formula identifies the positions used to calculate the median?

Accepted Answer

Average positions $$n/2$$ and $$(n/2)+1$$

Question 17

A group of 5 friends spends the following amounts on groceries: $$40, 45$$, $$45, 50$$, $220. What is the sample mean?

Accepted Answer

$$\frac{40+45+45+50+220}{5} = 80$$

Question 18

Which of the following best describes the graph in the second image (Most Popular Ways to Save for College)?

Accepted Answer

It is misleading because the size of the dollar signs exaggerates the differences between categories.

Question 19

A frequency distribution has the following class limits: 10-19, 20-29, 30-39, 40-49, 50-59. What is the class width?

Accepted Answer

$$10$$

Question 20

If a distribution is skewed right, which of the following is true?

Accepted Answer

$$	ext{Mean} \u003e 	ext{Median}$$

Introductory Statistics Test 1 Review – Step-by-Step Study Guidance

Guida di studio - Domande di pratica

Study guide - Flashcard