Intro Statistics

In a two-way table, what does the joint relative frequency represent?

• The frequency of a single category

• The total frequency of all categories

• The frequency of two categories occurring together

• The frequency of one category relative to the total

Answer explanation

The joint relative frequency in a two-way table indicates the frequency of two categories occurring together, providing insight into the relationship between them.

What is the difference between a population parameter and a sample statistic?

• A population parameter is a measure of a sample, while a sample statistic is a measure of a population.

• A population parameter is a measure of a population, while a sample statistic is a measure of a sample.

• Both are measures of a sample.

• Both are measures of a population.

Answer explanation

A population parameter refers to a characteristic of the entire population, while a sample statistic describes a characteristic of a sample drawn from that population. Thus, the correct choice accurately defines both terms.

Which of the following is an example of bivariate data?

• The number of books in a library

• The temperature and humidity levels in a greenhouse

• The types of trees in a forest

• The colors of cars in a parking lot

Answer explanation

Bivariate data involves two variables. The temperature and humidity levels in a greenhouse represent two related variables, making it an example of bivariate data. The other options represent single variables.

What is the term for the frequency of a single category relative to the total number of observations in a two-way table?

• Joint relative frequency

• Marginal relative frequency

• Conditional relative frequency

• Absolute frequency

Answer explanation

The term 'marginal relative frequency' refers to the frequency of a single category divided by the total number of observations in a two-way table, making it the correct choice for this question.

Which of the following best describes a model in statistics?

• A physical representation of a concept

• A theoretical framework to understand data

• A simulation of real-world processes

• A collection of raw data

Answer explanation

A model in statistics serves as a theoretical framework to understand data, helping to explain relationships and make predictions, rather than being just a physical representation, simulation, or raw data collection.

What is the term for the frequency of a category given the occurrence of another category in a two-way table?

• Joint relative frequency

• Marginal relative frequency

• Conditional relative frequency

• Absolute frequency

Answer explanation

The term 'conditional relative frequency' refers to the frequency of one category occurring given the occurrence of another category in a two-way table. It helps analyze the relationship between the two categories.

Which of the following is an example of continuous data?

• The number of students in a class

• The time it takes to run a marathon

• The type of car owned

• The number of siblings a person has

Answer explanation

Continuous data can take any value within a range. The time it takes to run a marathon is continuous, as it can vary in seconds and includes fractions. The other options are discrete data, representing counts or categories.

Which of the following best describes a sample in statistics?

• The entire group being studied

• A subset of the population being studied

• A measure of the entire population

• A theoretical model of the population

Answer explanation

A sample in statistics refers to a subset of the population being studied. It is used to make inferences about the entire population without needing to study every individual.

What is the primary purpose of using a random sample in statistics?

• To ensure the sample is larger than the population

• To make inferences about the population parameters

• To collect data from every individual in the population

• To avoid any form of bias in data collection

Answer explanation

The primary purpose of using a random sample is to make inferences about the population parameters. This allows statisticians to draw conclusions about the entire population based on the characteristics of the sample.

What is the term for a measure that summarizes a characteristic of a sample?

• Variable

• Data point

• Sample statistic

• Population parameter

Answer explanation

A sample statistic is a numerical measure that summarizes a characteristic of a sample, such as the mean or median. It contrasts with a population parameter, which describes a characteristic of the entire population.