Chapter 1 Learning Curve Questions

In a study of hospital births of people in a large metropolitan area, respondents were asked to report the time that the birth occurred on a specific day of the week. What is the individual in this description?

A person

What type of graph is used for categorical variables?

Bar Chart

If we asked people to classify their weight as underweight, normal, overweight or obese, would that variable be considered a categorical or quantitative variable?

Categorical

For research purposes, people were asked for the first 3 digits of their social security number (SSN). Would this variable be considered a categorical or quantitative variable?

Categorical → Since averaging the first 3 digits of a SSN doesn't have any meaning, we have to consider this a categorical variable. In addition, the first 3 digits give some indication of where the person lived when their SSN was issued.

A researcher counts the number of eggs a turtle has laid. True or False: This is a continuous variable.

FALSE This is a quantitative variable but it can only take whole number values (a turtle can't lay 1.5 eggs). The variable cannot take every value in an interval, so it is not a continuous variable. It is a discrete variable.

True or False: The distribution of a categorical value tells when the data was gathered and how it was collected.

False

True or False: Eye color in mice is an example of a discrete random variable.

False → Only quantitative variables can be discrete. Eye color is not a quantitative variable, it is a categorical random variable.

What type of graph is used for quantitative variables?

Histogram

A researcher is studying the eye color of mice. What type of variable is eye color in mice?

Nominal

Participants in a research study are asked to rate their energy level using the responses 0 to 5, with "0" indicating "very low energy" and "5" indicating "very high energy". What type of variable are these responses?

Ordinal → Although the participants give their answers as numbers, the rankings really represent the category they place themselves in. This is a categorical variable. The responses can be ordered from smallest to largest, so this is an ordinal variable.

Members of a health club were asked which classes they took at the club (Zumba, Step, P90, etc.). Why would it not be correct to display this data in a pie chart?

Some members may take more than one kind of class at the club.

For very large data sets it is best to plot the data using ________.

a histogram

A variable that places an individual into one of several groups is called a/an _________ variable.

categorical

qualitative variables are also called

categorical variable

A quantitative variable that can take any real numerical value within an interval is called a _______ variable.

continuous → A continuous variable can take any real numerical value within an interval. An example of this is the length of a flower stem.

quantitative variables are called

discrete

A histogram distribution that is skewed to the left looks like?

have tails on the left

A categorical variable whose values can be ranked is called a/an _______ variable.

ordinal