Q: Which of the following is the correct formula for calculating the proportion of observations in a category?

$$\text{Proportion} = \frac{\text{Frequency of the category}}{\text{Total number of observations}}$$

Question 1

Which of the following best describes a variable in statistics?

Accepted Answer

A variable is any characteristic of an individual that can take different values for different individuals.

Question 2

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

Accepted Answer

Type of residence (Apartment, Condo, House)

Question 3

Which of the following variables is quantitative and discrete?

Accepted Answer

Number of pets owned

Question 4

A researcher records the blood pressure of patients. What type of variable is blood pressure?

Accepted Answer

Quantitative, continuous

Question 5

Which of the following best describes the main feature of a categorical variable?

Accepted Answer

The percentage of observations in each category

Question 6

A frequency table lists the number of students who received each letter grade in a class. What is the proportion of students who received an 'A' if 8 out of 40 students received an 'A'?

Accepted Answer

$$0.20$$

Question 7

If the proportion of students who commute more than 10 km to school is $$0.15$$, what is the percentage of such students?

Accepted Answer

$$15\%$$

Question 8

Which of the following is NOT a quantitative variable?

Accepted Answer

Marital status

Question 9

A frequency table for daily TV watching shows that 232 out of 905 people watch 0–1 hours per day. What is the relative frequency (proportion) for this group?

Accepted Answer

$$0.256$$

Question 10

Which of the following best describes a continuous quantitative variable?

Accepted Answer

Possible values form an interval and can take any value within that interval

Question 11

A stock broker records whether a stock is up, the same, or down in value each day. What type of variable is this?

Accepted Answer

Categorical

Question 12

Which of the following is an example of a real-world scenario involving a discrete variable?

Accepted Answer

Counting the number of cars passing through a toll booth in an hour

Question 13

If 181 out of 905 people watch 4–5 hours of TV daily, what is the percentage of people in this group?

Accepted Answer

$$20.0\%$$

Question 14

Which of the following best describes the difference between descriptive and inferential statistics?

Accepted Answer

Descriptive statistics summarize data using graphical and numerical methods, while inferential statistics use data to make predictions or generalizations about a population.

Question 15

Which of the following is a key feature of a quantitative variable?

Accepted Answer

The center and spread (variability) of the data

Question 16

A survey asks for the first language spoken at home. What type of variable is this?

Accepted Answer

Categorical

Question 17

Which of the following is the correct formula for calculating the proportion of observations in a category?

Accepted Answer

$$	ext{Proportion} = \frac{	ext{Frequency of the category}}{	ext{Total number of observations}}$$

Question 18

Which of the following variables is best classified as continuous?

Accepted Answer

Length of time to take a test

Question 19

A frequency table shows that 44 out of 905 people watch 8 or more hours of TV daily. What is the proportion for this group?

Accepted Answer

$$0.049$$

Question 20

Which of the following is an example of a real-world application of a categorical variable?

Accepted Answer

Surveying patients about their type of residence (Apartment, Condo, House)

Data Types and Frequency Tables in Introductory Statistics

스터디 가이드 - 연습 문제

학습 가이드 - 플래시카드