Q: A researcher wants to estimate the proportion of voters who support a candidate. Which formula would be used to calculate the sample proportion $$\hat{p}$$?

$$\hat{p} = \frac{\text{number of voters supporting the candidate}}{\text{total number of voters surveyed}}$$

Question 1

Which of the following is a quantitative variable?

Accepted Answer

Customer satisfaction rating (on a 1-5 scale)

Question 2

A researcher wants to know the average amount spent by customers at a local bookstore. Which of the following best describes the population parameter of interest?

Accepted Answer

The mean amount spent by all customers at the bookstore

Question 3

Why might a researcher rely on a sample instead of a census?

Accepted Answer

A sample is often less costly and time-consuming than a census

Question 4

In the Pew Internet & American Life Project survey, 802 pairs of parents and teens were surveyed. Which of the following best describes the sample?

Accepted Answer

The 802 pairs of parents and teens surveyed

Question 5

A campaign director selects one block at random from each of NYC's five boroughs and interviews all residents found. What sampling method is being used?

Accepted Answer

Cluster sampling

Question 6

Which of the following is a potential source of bias in the campaign director's sampling method?

Accepted Answer

Interviewing only residents who are home at the time

Question 7

A local bookstore records the price of each transaction. Which variable is quantitative?

Accepted Answer

Price of the book

Question 8

A survey asks college students, 'How likely are you to buy an electric vehicle in the next ten years?' (scale of 1 = not at all likely to 5 = very likely). What type of variable is this?

Accepted Answer

Quantitative

Question 9

In the scenario where park managers hand out questionnaires only to parents who bring children to the park, what is the main problem with this sampling method?

Accepted Answer

It is likely to be biased toward parents who use the playground

Question 10

Which of the following best describes the population in the Zagat.com restaurant survey?

Accepted Answer

All customers who visited the restaurants in the past month

Question 11

A survey reports that 25% of teens primarily access the Internet on their cell phone. What is this value called?

Accepted Answer

Sample statistic

Question 12

Which of the following is NOT a plausible source of bias in a survey?

Accepted Answer

Using randomization in sample selection

Question 13

A researcher wants to estimate the proportion of voters who support a candidate. Which formula would be used to calculate the sample proportion $$\hat{p}$$?

Accepted Answer

$$\hat{p} = \frac{	ext{number of voters supporting the candidate}}{	ext{total number of voters surveyed}}$$

Question 14

If a bookstore records the Transaction ID for each purchase, is it economically significant that one Transaction ID is larger than another?

Accepted Answer

No, because Transaction IDs are identifiers and do not represent economic value

Question 15

Which of the following best describes a census?

Accepted Answer

A survey of all members of the population

Question 16

A survey asks, 'Do you think there will be more electric or gasoline powered vehicles on the road in 2030?' Which variable is being measured?

Accepted Answer

Qualitative variable

Question 17

In a survey, the average cost of a meal at a restaurant is reported. Which formula would be used to calculate the sample mean $$\bar{x}$$?

Accepted Answer

$$\bar{x} = \frac{\sum x_i}{n}$$

Question 18

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

Accepted Answer

Gift status (Y/N)

Question 19

A survey is conducted only among parents who bring their children to the park. What is the likely effect on the results?

Accepted Answer

Results will likely overestimate support for rebuilding the playground

Question 20

Which of the following best describes the 'What' in the W questions for a survey about electric vehicles?

Accepted Answer

The opinions and likelihood of buying electric vehicles

Question 21

A survey reports ratings of food, décor, and service on a 30-point scale. What type of variable are these ratings?

Accepted Answer

Quantitative

Step-by-Step Guidance for Introductory Statistics Quiz (Chapters 1 & 8)

스터디 가이드 - 연습 문제

학습 가이드 - 플래시카드