Exam 10: Hypothesis Testing, Effect Size, and and Confidence Intervals: Two-Sample Designs

Data Set 10-6: Drugs used in treating schizophrenia all block the reception of dopamine by neurons. (Dopamine is a neurotransmitter, which, when released by the axons of one nerve, inhibits the firing of the next nerve.) This fact led to the idea that schizophrenia occurs when too much dopamine is produced. Suppose the following data on dopamine production were obtained. Schizophrenics Control Group 42 33 31 27 29 18 -The study described in Data Set 10-6 is an example of

In the simple experiment described by your text, extraneous variables were controlled using random assignment.

If you find that there is a logical reason to pair the scores from the two groups in a two-group experiment, you know whether

The null hypothesis states that the sample means are identical.

The t test was developed as a way to analyze data from experiments with rats in mazes.

The null hypothesis in a paired samples t test is that the two

If the t distribution is to produce an accurate probability figure, which of the following must be true?

Data Set 10-3: An experimenter matched by weight four pairs of volunteers. One member of each pair was randomly assigned to one of the two groups. One group fasted for 24 hours and the other for 48 hours. Scores below represent the number of ounces of Yummi (very vanilla) consumed during the first 10 minutes after the fast. Test for a difference at the .05 level. 24 hours 48 hours 26 18 35 24 23 17 30 14 -The conclusion from Data Set 10-3 is that

Null hypothesis statistical testing (NHST) allows you to conclude that the null hypothesis is

Suppose an experimenter established a 95 percent confidence interval about the difference between two sample means and found values of -1.35 and +1.35. The null hypothesis should be

A student conducted a before and after study on college statistics students to see if the course improved ability to reason. In a later study, she used a mother-daughter sample to assess generational differences in attitudes toward abortion. Her two designs are

As________ and____________ increase, a statistical test becomes more powerful.

If the t distribution is to produce an accurate probability figure for an independent-samples t test, which of the following must be true?

In a simple experiment, treat two groups exactly the same except for one thing and then measure the individuals in both groups on some scale. Treating the two groups differently on the one thing constitutes

Identify the following as paired samples or independent samples. In each case, give the appropriate df. -The attitudes toward plagiarism of 21 famous psychologists were compared to those of each one's designated "best student."

Which of the following statements is most closely related to confidence intervals?

Values of d greater than 1.00 indicate a large effect size.

Which of the following statements uses the statistical definition of "significant"?

Degrees of freedom are most closely related to

Data Set 10-1: A college teacher was assigned 4 freshmen advisees. He administered an attitude scale that measured liberalism-conservatism. Four years later, just before graduation, all 4 took the same scale again. High scores indicate conservative attitude. The following scores were obtained. 2006 2010 26 15 22 23 17 14 15 10 -The standard error of the difference for Data Set 10-1 is