Q: Given the following counts of Titanic passengers by class: First (325), Second (285), Third (706), Crew (885), what is the relative frequency (percentage) of Third Class passengers? (Round to two decimal places)

$$ \frac{706}{2201} \times 100 = 32.08\% $$

Q: In a study, 68 out of 200 high school graduates, 112 out of 200 college graduates, and 152 out of 200 university graduates support green infrastructure investment. What is the conditional distribution (as a percentage) of support among university graduates?

$$ \frac{152}{200} \times 100 = 76\% $$

Question 1

Which of the following best describes the primary purpose of statistics as introduced in ENVS 178?

Accepted Answer

To understand and model variation in data to reveal patterns and inform decision-making.

Question 2

Which of the following is NOT one of the five W’s essential for providing context to data?

Accepted Answer

Which

Question 3

A researcher collects the heights (in centimeters) of all students in a class. What type of variable is 'height'?

Accepted Answer

Quantitative variable

Question 4

In a survey, students are asked to rate their agreement with a statement on a scale from 1 (Disagree Strongly) to 5 (Agree Strongly). What type of variable is this?

Accepted Answer

Ordinal variable

Question 5

Which of the following is an example of an identifier variable?

Accepted Answer

Social Insurance Number

Question 6

Why is it important to consider 'how' data are collected when analyzing a dataset?

Accepted Answer

Because the method of data collection can introduce bias and affect the validity of conclusions.

Question 7

Which of the following best illustrates the area principle in data visualization?

Accepted Answer

The area of each section in a pie chart is proportional to the percentage it represents.

Question 8

A frequency table is used to:

Accepted Answer

Record the totals for each category of a categorical variable.

Question 9

Given the following counts of Titanic passengers by class: First (325), Second (285), Third (706), Crew (885), what is the relative frequency (percentage) of Third Class passengers? (Round to two decimal places)

Accepted Answer

$$ \frac{706}{2201} 	imes 100 = 32.08\% $$

Question 10

Which of the following is TRUE about bar charts and pie charts?

Accepted Answer

Pie charts are useful when you want to show parts of a whole and categories are mutually exclusive.

Question 11

A contingency table is used to:

Accepted Answer

Show the relationship between two categorical variables.

Question 12

If the conditional distribution of one variable is the same for every category of another variable in a contingency table, what can we conclude?

Accepted Answer

The variables are independent.

Question 13

In a study, 68 out of 200 high school graduates, 112 out of 200 college graduates, and 152 out of 200 university graduates support green infrastructure investment. What is the conditional distribution (as a percentage) of support among university graduates?

Accepted Answer

$$ \frac{152}{200} 	imes 100 = 76\% $$

Question 14

Which of the following is a potential pitfall when interpreting percentages in a statistical report?

Accepted Answer

Confusing similar-sounding percentages without considering the context.

Question 15

A segmented bar chart is most useful for:

Accepted Answer

Comparing conditional distributions across categories.

Question 16

Which of the following statements about data collection is correct?

Accepted Answer

Randomness in sampling is more important than sample size for reducing bias.

Question 17

Suppose a pie chart is drawn with a 3D effect and a slant. What is a likely problem with this visualization?

Accepted Answer

It violates the area principle, making it harder to compare proportions accurately.

Question 18

Which of the following is NOT a recommended step when beginning any data analysis?

Accepted Answer

Ignore the context of the data.

Question 19

A study reports that 66.67% of rats improved performance with training, but only three rats were studied. What is the main issue with this report?

Accepted Answer

The sample size is too small to draw meaningful conclusions.

Question 20

Which of the following best describes a marginal distribution in a contingency table?

Accepted Answer

The distribution of one variable, ignoring the categories of the other variable.

Introduction to Statistics: Understanding and Displaying Categorical Data

스터디 가이드 - 연습 문제

학습 가이드 - 플래시카드