Q: If a frequency table lists the number of observations and the relative frequencies for each value, what is the formula for calculating the relative frequency (proportion) for a category?

$$\text{Relative\ Frequency} = \frac{\text{Frequency\ in\ category}}{\text{Total\ number\ of\ observations}}$$

Question 1

Which of the following best describes a variable in statistics?

Accepted Answer

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 best classified as a discrete quantitative variable?

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

Continuous quantitative

Question 5

Which of the following is NOT a key feature of a quantitative variable?

Accepted Answer

Percentage of observations in each category

Question 6

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

Accepted Answer

Categorical

Question 7

Which of the following best describes a frequency table?

Accepted Answer

A table listing possible values for a variable, with the number of observations and/or relative frequencies for each value.

Question 8

If 4 students received an 'A' out of 40 students, what is the proportion of students who received an 'A'?

$$	ext{Proportion} = \frac{	ext{Number of 'A's}}{	ext{Total students}}$$

Accepted Answer

$$0.10$$

Question 9

Given the same scenario, what is the percentage of students who received an 'A'?

$$	ext{Percentage} = 	ext{Proportion} 	imes 100$$

Accepted Answer

$$10\%$$

Question 10

Which of the following is a real-world example of a continuous variable?

Accepted Answer

Length of time (in minutes) to take a test

Question 11

A frequency table for daily TV watching shows that 232 people watch 0–1 hours, 403 watch 2–3 hours, 181 watch 4–5 hours, 45 watch 6–7 hours, and 44 watch 8 or more hours. What is the total number of observations?

Accepted Answer

$$232 + 403 + 181 + 45 + 44 = 905$$

Question 12

Which of the following best describes the difference between discrete and continuous quantitative variables?

Accepted Answer

Discrete variables can only take on a finite or countable number of values, while continuous variables can take on any value within an interval.

Question 13

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

Accepted Answer

Categorical

Question 14

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

Accepted Answer

The percentage of observations in each category

Question 15

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

Accepted Answer

Age (in years)

Question 16

If a frequency table lists the number of observations and the relative frequencies for each value, what is the formula for calculating the relative frequency (proportion) for a category?

Accepted Answer

$$	ext{Relative\ Frequency} = \frac{	ext{Frequency\ in\ category}}{	ext{Total\ number\ of\ observations}}$$

Question 17

Which of the following best describes descriptive statistics?

Accepted Answer

The summarization of data using graphical and numerical methods.

Question 18

A hospital records the number of patients admitted each day. What type of variable is this?

Accepted Answer

Quantitative, discrete

Question 19

Which of the following is a correct calculation for the percentage of observations in a category if the proportion is $$0.25$$?

Accepted Answer

$$0.25 	imes 100 = 25\%$$

Lesson 3.1

스터디 가이드 - 연습 문제

학습 가이드 - 플래시카드