Exam 1: Introduction to Statistics

After measuring two individuals,a researcher can say that Tom's score is 4 points higher than Bill's.The measurements must come from a(n)_______ scale.

A correlational study is used to examine the relationship between two variables but cannot determine whether it is a cause-and-effect relationship.

The goal for an experiment is to demonstrate that changes in one variable are responsible for causing changes in a second variable.

What is the value of Σ(X + 1)for the scores 1,0,1,4?

Classifying people into two groups on the basis of gender is an example of measurement on an ordinal scale.

A discrete variable must be measured on a nominal or an ordinal scale.

For the following scores,Σ(X + 1)= 9.

A recent study reports that students who just finished playing a prosocial video game were more likely to help others than students who had played a neutral or antisocial game.For this study,what is the independent variable?

A correlational study typically uses only one group of participants but measures two different variables (two scores)for each individual.

Organizing a set of scores in a table is an example of using _______.

Using the election results from a sample of n = 100 voters to predict the results for the entire state is an example of inferential statistics.

Which of the following is done last in the order of operations?

What is the value of (ΣX)² for the scores 1,0,2,4?

The average verbal SAT score for the entire class of entering freshmen is 530.However,if you select a sample of 20 freshmen and compute their average verbal SAT score you probably will not get exactly 530.What statistical concept is used to explain the natural difference that exists between a sample mean and the corresponding population mean?

A researcher is interested in the eating behavior of rats and selects a group of 25 rats to be tested in a research study.The group of 25 rats is an example of a ______.

Define the concept of "sampling error." Note: your definition should include the concepts of sample,population,statistic,and parameter.

A researcher records the change in weight (gain or lost)during the first semester of college for each individual in a group of 25 freshmen and calculates the average change in weight.The average is an example of a _______.

What additional information is obtained by measuring two individuals on an ordinal scale compared to a nominal scale?

A researcher is interested in the average income for registered voters in the United States.The entire group of registered voters is an example of a population.

For statistical purposes,there usually is not much reason to differentiate between interval and ratio scales.