Dr. Jordan believes there is a relationship between the amount of chocolate a child eats and the hyperactivity level of the child. This belief is a(n) A. theory B. variable C. paradigm D. hypothesis E. premise
A. theory
Luis conducted a study of the attitudes and savings behavior. He followed 100 participants for 10 years. Luis conducted a ________________ study. A. longitudinal B. ex-post facto C. experimental D. cross-sectional E. cross-sequential
A. longitudinal
Which of the following coefficients of a correlation indicate the weakest relationship between two variables? A. 0.51 B. -0.28 C. 0.08 D. -1.00 E. 1.00
C. 0.08
Cyril Burt’s work on I.Q. and class is a famous example of this bias. The psychologist worked on a study in the 1960’s to prove the heritability of the I.Q. He assumed that children from working class had a lower I.Q. and that children from higher social class had a higher I.Q. Unsurprisingly, his study “confirmed” that children from working class were less intelligent. It was later found that this finding was incorrect, and a likely reason for this mistake was his expectation of this finding changing how these children acted. This demonstrates A. the placebo effect in a natural experiment B. observer expectancy bias C. hindsight bias D. the ethical problems of field experiments
B. observer expectancy bias
In an experiment, the variable that is manipulated is called the _________________variable. A. control B. independent C. dependent D. extraneous E. confounding
B. independent
In a normal distribution of scores, approximately what percentage of all scores will occur within one standard deviation from the mean? A. 34 B. 68 C. 95 D. 97.5 E. 100
B. 68
Cory scored high on a test of mathematics. He also scored high on a test of engineering. If we run a correlation on his scores, the correlation would be _______ A. perfect B. positive C. negative D. skewed E. no relationship
B. positive
In a weight-reduction experiment, an overweight individual was given what the researcher called a new type of diet pill that would help curb the desire to eat. In fact, the pill really contained powdered milk, but ever since the individual started taking the diet pill, he has reported that his desire to eat has decreased. This illustrates the A. linear relationship B. effect of extraneous variables C. natural experiment D. placebo effect
D. placebo effect
Dexter works for a magazine and is told by his editor to write an article on test scores in the local elementary school. He divides the students into groups based on grade level. He then examines the local test scores. In this study, the dependent variable is the ____________. A. school the students attend B. grade level of the students C. income level of the parents D. gender of the students E. test scores of the students
E. test scores of the students
Psychologists use statistics to determine if the differences we find are statistically significant. The p-value must be:
A. Greater than 0.01
B.Greater than 0.05
C. Less than 0.01
D. Less than 0.05
D. Less than 0.05
The correlation between two observed variables is -0.84. From this, it can be concluded that A. as one variable increases, the other is likely to increase, showing a direct relationship B. as one variable increases, the other is likely to decrease, showing an inverse relationship C. the two variables are unrelated D. one variable causes the other variable to occur E. one variable causes the other variable not to occur
B. as one variable increases, the other is likely to decrease, showing an inverse relationship
A measure of central tendency for a distribution, represented by the score that occurs more often than any other. A. median B. mode C. mean D. variability E. standard deviation
B. mode
Dr. Bisell conducts an experiment to see whether hunger makes mice run faster through a maze. He randomly assigns 25 mice to a control group or an experimental group. Which cannot be a confounding variable? A. Where the experiment takes place B. How hungry the mice were before the experiment C. How fast the mice are before the race D. When the experiment takes place E. The population from which he selected the mice
E. The population from which he selected the mice
No statistical model is perfect. __________refers to non-random effects caused by some factor outside the research hypothesis.
A. Error
B. Variability
C. Bias
D. Reliability
C. Bias
A researcher determines that the crime rate in a large city fluctuates with the phases of the moon. He concludes that the gravitational pull of the moon influences human behavior. He has committed what error? A. He incorrectly inferred correlation from causation. B. He incorrectly inferred causation from correlation. C. He failed to measure the gravitational pull to test his hypothesis. D. He has overlooked the placebo effect.
B. He incorrectly inferred causation from correlation.
___________________is the tendency to believe after learning an outcome, that one would have foreseen it. A. illusory correlation B. hindsight bias C. overconfidence D. critical thinking E. skepticism
B. hindsight bias
A random sample can best be defined as: A. A sample in which each potential participant has an equal chance of being selected B. A sample that is carefully chosen so the characteristics of participants correspond to the larger population C. A selection of cases from a larger population D. A selection of cases from the control group E. A sample of a larger population from the experimental group
A. A sample in which each potential participant has an equal chance of being selected
This is a measure of variability under a normal curve A. mean. B. median. C. mode. D. standard deviation. E. range.
D. standard deviation
An observation that the higher the air temperature, the lower the activity of test animals would be an example of a A. negative correlation B. positive correlation C. causal relationship D. zero correlation
A. negative correlation
The phenomenon that is a variable is extreme on the first measurement, it will tend to be closer to the mean on its second measurement. A. positive regression B. regression toward the mean C. standard regression D. negative regression E. inferential statistics
B. regression toward the mean