PSY 290

A psychological study finds a correlation coefficient of r = .63. What does this tell you about the magnitude of this effect?

• It is very small or very weak.

• It is small or weak.

• It is moderate.

• It is unusually large in psychology.

Imagine that you are discussing a research study with a friend, and that person asks whether the variables in an association claim are measured appropriately.  What type of validity is your friend concerned about?

• construct validity

• external validity

• internal validity

• statistical validity

Temporal precedence is also known as the ________ problem.

• third variable

• covariance

• association

• directionality

Which of the following situations would be especially problematic when using a correlation coefficient (r) to evaluate an association between two variables?

• The two variables have a strong curvilinear relationship.

• The two variables do not have statistical validity.

• The two variables may be affected by a third variable.

• A correlation coefficient cannot detect negative relationships.

Outliers can have a dramatic effect on the correlation coefficient between two variables. In which of the following circumstances are outliers likely to have the biggest impact?

• When the sample size is small.

• When the direction of the relationship is negative.

• When they represent a majority of the data points.

• When the relationship is otherwise non-existent.

Imagine that you have collected information on parental status (parent vs. not a parent), which is a categorical variable. You have also collected information on life satisfaction (a continuous quantitative variable). Which of the following graphs is the best way to show an association between these variables?

• Scatterplot

• Line Graph

• Bar Graph

• Pie Chart

Imagine that you are reading about a research study.  Which of the following design characteristics would indicate that the authors are making an association claim? 

• The study has one manipulated and one measured variable

• The study has two measured variables

• The study has two manipulated variables

• The study has two categorical variables

A small effect might still be important in which of the following scenarios?

• when the sample is very large

• when it is aggregated over many situations

• when the outcome is extreme, like success or failure

• when external validity is high

When evaluating the external validity of an association claim, which of the following is the most important issue to consider?

• the way the sample was selected from the population

• the size of the sample

• the number of subgroups

• the size of the original population

Which of the following represents the best reason why someone interested in making a causal claim would do something other than an experiment?

• Experiments are very expensive, and the researcher might not have grant funding.

• There may be ethical limitations of manipulating a variable.

• Laboratory space is required for experiments, and the researcher might not have a lab.

• Experiments take longer to do than other types of studies.