Reida has developed a program that is designed to increase the reading comprehension scores of sixth graders. She randomly selects three students to participate in her program. When she compares the mean score of the students who completed her program to that of three students who did not participate in the program, she finds no significant difference between the mean scores. What is most likely the reason for the nonsignificant finding?

A professional baseball scout uses the batting average, on-base percentage, throwing ability, and running speed of amateur baseball players to predict their success as professional baseball players. This scenario best exemplifies the use of ________ as a predictor of the likelihood of success.

Identify the risk associated with a pretest.

A failure to replicate could mean that the

Which of the following statements is true of exact replications?

A researcher replicates a past study that manipulates the physical attractiveness of a defendant by using photographs instead of written descriptions. This technique is  an example of a(n) ________ replication.

Which of the following statements is true about error variance?

Which statistical test would be most appropriate for examining the relationship between temperature and the number of ice cream cones sold?

A researcher assesses the length of the prison sentence for physically attractive and physically unattractive defendants. He believes that attractive defendants will receive shorter prison sentences than unattractive defendants. The null hypothesis would suggest that

A researcher wants to test a hypothesis according to which the mean rating of guilt will be higher for unattractive defendants than for attractive defendants. The appropriate statistical test would be the