Contingency Tables and Marginal Distribution

This video introduces contingency tables, a tool for displaying data from surveys with two variables, each having multiple categories. It explains how to count responses, calculate totals, and understand marginal distribution by converting counts into percentages. The video provides a comprehensive overview of how to analyze survey data using contingency tables.

What is the primary purpose of using a contingency table?

• To predict future survey outcomes

• To calculate the average of survey responses

• To show the relationship between two variables with multiple categories

• To display the count of responses for a single question survey

In the survey example, what are the two questions asked?

• What is your gender and what is your political party?

• What is your age and what is your favorite color?

• What is your income level and what is your education level?

• What is your occupation and where do you live?

How many total people were surveyed in the example provided?

• 130

• 120

• 150

• 100

What is the total number of Democrats in the survey?

• 60

• 51

• 42

• 37

How do you calculate the total number of males surveyed?

• Divide the total number of males by the total number of females

• Multiply the number of male Democrats by the number of male Republicans

• Subtract the number of female Democrats from the total number of Democrats

• Add the number of male Democrats, Republicans, and Independents

What is marginal distribution?

• The percentage of each category in the margin of a contingency table

• The average response rate in a survey

• The total count of responses in a survey

• The distribution of a single variable in a survey

How is the percentage of Democrats calculated in the marginal distribution?

• By subtracting the number of Independents from the total surveyed

• By dividing the number of Democrats by the number of Republicans

• By multiplying the number of Democrats by 100

• By dividing the number of Democrats by the total surveyed and multiplying by 100

What percentage of the surveyed individuals identified as Republicans?

• 42.0%

• 39.2%

• 32.3%

• 28.5%

Which section of the contingency table helps in understanding the marginal distribution?

• The center of the table

• The bottom margin

• The right margin

• The top row

What is the key takeaway about contingency tables from the video?

• They are primarily used for financial data analysis

• They are only useful for single-variable analysis

• They help in understanding the relationship between two variables

• They are used to predict future trends