psych october 1 practice multiple choice

r vs p

r is correlation coefficient and p is statistically significant variable

Which of the following correlations coefficients most likely represents the relationship between length of sleep deprivation and level of alertness? 1.35 0.85 0.01 -0.4 -1.25

-0.4

In a normal distribution, approximately what percent of the scores occur within one standard deviation above and below the mean?

68%

Researchers have found a negative correlation between income and dental problems. What conclusion can correctly be drawn from this statement?

As income increases, the likelihood of dental problems decreases

According to research on interpersonal perception, the formation of friendships is associated with which of the following? Physical attractiveness Physical proximity attributions of similarity

I, II, and III

One graph is tall and narrow and one is flat and wide. Which one has more variation?

The flat one

A research design involves two randomly assigned groups of participants. One group receives a one-time treatment, and the other does not. Later, the two groups are compared to see whether the treatment had an effect. Psychologists call this kind of research

an experiment

The correlation between scores obtained on two halves of a single test yields information about the test's.

reliability

A researcher interested in finding a simple way to estimate intelligence decides to evaluate skull circumference as a possible indicator of intelligence. He finds that the size of an adult's skull remains the same form one measurement to the next, but he finds that skull circumference is not a very good predictor of intelligence. In this example, skull circumference as a measure of intelligence is reliable and valid reliable but not valid valid but not reliable neither reliable nor valid highly correlated with intelligence test scores

reliable but not valid

A researcher surveyed social adjustment in the same group of 20 people from early childhood through adulthood. In this example, the group of 20 people surveyed was the study's

sample

Research shows that women who are referred by a physician to participate in a study of eating disorders have more severe problems than women who volunteer on their own to participate in the study. If research on eating disorders regularly involves only women referred by physicians, the results of the studies might be limited because of the presence of

sampling bias

Standard deviation is a measure of how much

scores in a group differ from the mean of that group

Researchers find that there is a significant, positive correlation between the number of hours students sleep and their grades. The researchers would be justified in concluding that

students who earn good grades tend to sleep more than those who do not

The researcher's conclusion that p = .05 most likely indicates

that the difference between the two groups is statistically significant

The results of a correlational study involving student volunteers in a psychology laboratory might not apply to the general population because

the sample is not randomly chosen and therefore may not be a representative sample

Which of the following best describes the response of members of the American Psychological Association to ethical issues in research?

they have developed codes of ethics for research with both human participants and animal subjects