Question 1

Which of the following best describes the difference between a parameter and a statistic?

Accepted Answer

A parameter is a numerical summary of a population, while a statistic is a numerical summary of a sample.

Question 2

A researcher wants to estimate the average salary of all engineers in a city. She randomly selects 100 engineers and calculates their average salary. What is this average called?

Accepted Answer

Sample mean

Question 3

Which of the following is an example of qualitative data?

Accepted Answer

The eye color of students

Question 4

A company surveys every 10th customer who enters their store to assess satisfaction. Which sampling method is being used?

Accepted Answer

Systematic sampling

Question 5

Which of the following is a discrete quantitative variable?

Accepted Answer

The number of goals scored by a soccer team in a match

Question 6

A school wants to select a sample of students such that every student has an equal chance of being chosen. Which sampling method should they use?

Accepted Answer

Simple random sampling

Question 7

Which of the following scenarios best illustrates an observational study?

Accepted Answer

A manager records employees' sleep habits without changing anything.

Question 8

A researcher divides a population into groups based on age and then randomly selects subjects from each group. What sampling method is this?

Accepted Answer

Stratified sampling

Question 9

Which of the following is NOT a quantitative variable?

Accepted Answer

The nationality of students

Question 10

A manager wants to know if increasing store hours increases profits. She randomly selects half of her stores and increases their hours, then compares profits to the other half. What type of study is this?

Accepted Answer

Experiment

Question 11

Which of the following best describes a representative sample?

Accepted Answer

A sample that reflects the characteristics of the entire population

Question 12

A quality control manager selects every 20th item produced on a factory line for inspection. What sampling method is this?

Accepted Answer

Systematic sampling

Question 13

Which of the following statements about causation is TRUE?

Accepted Answer

Experiments can provide evidence for causation.

Question 14

A bakery wants to select 12th customer each day for a survey. Which sampling method is this?

Accepted Answer

Systematic sampling

Question 15

A regional manager wants to survey employees at three locations of a chain restaurant. She randomly selects one location and surveys all employees there. What sampling method is this?

Accepted Answer

Cluster sampling

Question 16

Which formula would you use to calculate the mean of a sample?

Accepted Answer

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

Question 17

A survey of all registered voters in a country finds that 48% are registered Democrats. Is this a parameter or a statistic?

Accepted Answer

Parameter

Question 18

A college professor wants feedback from her statistics course and decides to survey 5 random students out of the 20. Which process is best for generating a simple random sample of 5 out of 20 students?

Accepted Answer

Assign each student a number and use a random number generator to select 5 unique numbers.

Question 19

Which of the following is an example of continuous quantitative data?

Accepted Answer

The time (in seconds) it takes to run a race

Question 20

A report shows the amount (in dollars) spent by each customer in a grocery store. Is this data set a population or sample?

Accepted Answer

Sample

Intro to Statistics and Collecting Data: Study Notes

스터디 가이드 - 연습 문제

학습 가이드 - 플래시카드