Q: Which of the following is a correct formula for the relative frequency of a class in a frequency distribution?

$$ \text{Relative frequency} = \frac{\text{Frequency of the class}}{\text{Total number of observations}} $$

Question 1

Which of the following best describes the difference between a population and a sample in statistics?

Accepted Answer

A population is the entire group of interest, while a sample is a subset of the population that is actually observed.

Question 2

Suppose you want to estimate the average salary of all employees in a large company. You collect data from 50 randomly selected employees. In this context, what is the parameter?

Accepted Answer

The average salary of all employees in the company.

Question 3

Which of the following is an example of inferential statistics?

Accepted Answer

Using a sample mean to estimate the average income of all households in a city.

Question 4

A researcher collects data on the number of cars parked on a street each day for a month. What type of variable is 'number of cars'?

Accepted Answer

Discrete numerical

Question 5

Which of the following sampling methods ensures that every possible sample of size $$n$$ from a population has an equal chance of being selected?

Accepted Answer

Simple random sampling

Question 6

A survey asks respondents to rate their satisfaction as 'low', 'medium', or 'high'. What is the level of measurement for this variable?

Accepted Answer

Ordinal

Question 7

Which of the following is a non-sampling error?

Accepted Answer

Survey non-response due to sensitive questions

Question 8

In the context of the 1936 US Presidential Election, why did the Literary Digest poll fail to predict the correct winner?

Accepted Answer

The poll suffered from coverage error due to sampling from non-representative lists.

Question 9

Which of the following graphs is most appropriate for displaying the distribution of a categorical variable such as 'favorite fruit'?

Accepted Answer

Bar chart

Question 10

A company wants to compare the frequency of different types of product defects. Which graphical tool should they use to highlight the most common defects?

Accepted Answer

Pareto diagram

Question 11

Which of the following best describes a time-series plot?

Accepted Answer

A line chart with time on the horizontal axis and the variable of interest on the vertical axis

Question 12

If a histogram of task completion times is highly skewed to the right, what does this indicate about the data?

Accepted Answer

Most employees completed the task in a short time, but a few took much longer.

Question 13

Which of the following is a correct formula for the relative frequency of a class in a frequency distribution?

Accepted Answer

$$ 	ext{Relative frequency} = \frac{	ext{Frequency of the class}}{	ext{Total number of observations}} $$

Question 14

A scatterplot is used to:

Accepted Answer

Display the relationship between two numerical variables

Question 15

Which of the following statements about descriptive and inferential statistics is correct?

Accepted Answer

Descriptive statistics summarize data, while inferential statistics use data to make predictions or decisions about a population.

Question 16

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

Accepted Answer

Temperature measured in degrees Celsius

Question 17

A company collects data on the annual income of its employees and wants to display the distribution. Which graphical method is most appropriate?

Accepted Answer

Histogram

Question 18

Which of the following best describes the purpose of a stem-and-leaf display?

Accepted Answer

To display the distribution of a numerical variable while preserving the original data values

Question 19

In a study, researchers find that as years of education increase, average income also increases. What type of association is this?

Accepted Answer

Positive association

Question 20

Which of the following is a potential source of response bias in a survey?

Accepted Answer

Asking sensitive questions about income

Chapter 1: Using Graphs to Describe Data – Study Notes for Statistics for Business

Guida di studio - Domande di pratica

Study guide - Flashcard