Question 1

The number of students in a class is an example of discrete,quantitative data.

Accepted Answer

The number of students in a class can only be a whole number, which means it is discrete. Additionally, it is a numerical measurement, which makes it quantitative. Therefore, the statement is true.

Question 2

A rating scale measurement from 1 (completely disagree)to 7 (completely agree)is an example of continuous,qualitative data.

Accepted Answer

A rating scale measurement is an example of discrete, ordinal data because the responses are limited and in order, rather than continuously measurable.

Question 3

Continuous data are only distributed in discrete units.

Accepted Answer

Continuous data is distributed in a continuum, meaning that it can take on any value within a certain range, without any discrete units. On the other hand, discrete data can only take on certain values, typically whole numbers or categories.

Question 4

Children received grapefruit juice mixed with 2%,5%,or 10% sugar to test whether higher concentrations of sugar can enhance liking for the taste of grapefruit juice.In this example,the sugar mixtures are the independent variable.

Accepted Answer

The sugar mixtures are being manipulated in order to see how they affect liking for grapefruit juice, making them the independent variable.

Question 5

The political affiliation of participants (Democrat,Republican)is an example of discrete,qualitative data.

Accepted Answer

This is because political affiliation can only take on a finite number of values (Democrat or Republican) and is not a continuous variable. It is also qualitative because it is a characteristic or attribute of the participants, rather than a numerical measurement.

Question 6

Only an experiment can demonstrate cause-and-effect relationships between variables.

Accepted Answer

This is because an experiment involves manipulating one variable (the independent variable) while keeping all other factors (the dependent variable and extraneous variables) constant, and then observing the effect on the dependent variable. This allows for the identification of cause-and-effect relationships between variables. Other research designs, such as correlational studies, can only identify relationships between variables but cannot establish causation.

Question 7

A student's letter Grade (A,B,C,D,F)is a nominal scale measurement.

Accepted Answer

The answer of A student's letter Grade (A,B,C,D,F)is a nominal...

Question 8

The size of a reward (in grams)is an example of continuous,quantitative data.

Accepted Answer

Continuous data is measured on a continuous scale and includes all numbers between certain values. In this case, the size of a reward can have any value between certain minimum and maximum values, making it an example of continuous data. Quantitative data refers to numerical measurements or quantities, which is also applicable in this case.

Question 9

The duration of attention (in seconds)is a ratio scale measurement.

Accepted Answer

The duration of attention can be measured on a ratio scale because it has a true zero point and differences between values are meaningful. For example, if one person pays attention for 10 seconds and another person pays attention for 20 seconds, we can say that the second person paid attention for twice as long as the first person.

Question 10

Researchers who measure qualitative variables can also measure those that are quantitative in the same study.

Accepted Answer

Qualitative variables are often measured using categorical data, while quantitative variables involve numerical measurements. However, it is possible for researchers to collect both types of data in the same study, depending on their research question and design. For example, a study could investigate the relationship between gender (a qualitative variable) and income (a quantitative variable) by collecting data on both variables from study participants.

Question 11

A score on a multiple-choice exam (0-100 points)is a ratio scale measurement.

Accepted Answer

A score on a multiple-choice exam can be considered a ratio scale measurement because it has a true zero point (0 points) and equal intervals between numbers (each point represents an equal amount of achievement or knowledge).

Question 12

A researcher observes the number of tasks completed by male and female participants during a multitasking observation period.In this example,sex (male,female)is the quasi-independent variable.

Accepted Answer

The statement is true. Sex (male, female) is a quasi-independent variable as it is not manipulated by the researcher, but it is still an important variable that can affect the outcome of the study.

Question 13

In some cases,the number of participants in a sample can be greater than the number of persons in the population from which the same was selected.

Accepted Answer

The number of participants in a sample cannot exceed the total number of individuals in the population from which the sample is drawn, as the sample is a subset of the population.

Question 14

A categorical variable is an example of discrete data.

Accepted Answer

A categorical variable is one that falls into distinct categories or groups, and thus represents discrete data.

Question 15

The weight (in pounds)of a newborn infant is an interval scale measurement.

Accepted Answer

Interval scale measurements have equal intervals between values but no true zero point. Weight has a true zero point, making it a ratio scale measurement.

Question 16

Children are randomly assigned to complete a low,moderate,or high difficult task.The time (in seconds)it takes them to complete the task is recorded.In this example,the level of task difficulty is the dependent variable.

Accepted Answer

The level of task difficulty is the independent variable because it is being manipulated to observe its effect on the dependent variable, which is the time it takes for the children to complete the task.

Question 17

A researcher records the number of alcoholic drinks consumed per week by students living on campus in rural and urban colleges.In this example,the number of alcoholic drinks consumed per week is the dependent variable.

Accepted Answer

The dependent variable is the variable being measured, which in this case is the number of alcoholic drinks consumed per week. The independent variable would be the type of college (rural vs urban).

Question 18

Qualitative data are nonnumeric data.

Accepted Answer

Qualitative data are descriptive and cannot be measured or expressed numerically. Examples include colors, smells, tastes, and opinions.

Question 19

A professor measures the number of review sessions attended per week and GPA in a sample of college freshmen and concludes that increased attendance for review sessions is related to higher grades.This research design is an example of an experimental design.

Accepted Answer

The statement describes an observational study with no manipulation of variables, therefore it is not an experimental design. The conclusion drawn from observational studies cannot establish causality.

Question 20

An interval scale of measurement is generally more informative than an ordinal scale of measurement.

Accepted Answer

An interval scale of measurement not only allows us to order data, but also allows us to make meaningful comparisons between the values. On the other hand, an ordinal scale only allows us to rank data in a specific order without any information about the magnitude of differences between the values. Therefore, an interval scale is generally more informative than an ordinal scale.

Quiz 1: Introduction to Statistics