exam 2 POS

1.        What does it mean random sampling of participants?

• It means that the causal conclusions reached in the study about the relationship between X and Y are scientifically valid.

• It means that every member of the population was given the opportunity to participate in the study.

• It means that the results are more likely to be statistically significant.

• Every member of the population has an equal chance of being selected to participate in a study

What is the difference of random sampling and random assigning?

• Random assignment is when the participants for an experiment are assigned randomly to one of the several possible values of the independent variable. Random samplings a method of selecting individuals cases for a study in which every member of the underlying population has an equal probability of being selected.

• Random assignment is a method of selecting individuals cases for a study in which every member of the underlying population has an equal probability of being selected. Random sampling is when the participants for an experiment are assigned randomly to one of the several possible values of the independent variable.

Which of the following best captures the difference between experimental observational research designs

• Experimental designs control for confounding variables through randomly assigning participants to different treatment groups, while observational designs accomplish this through statistical controls.

• Experimental designs are less prone than observational designs to bias caused by a researcher unintentionally influencing the behaviors of participants

• Reverse causality is more likely to be problematic in experimental designs.

• Experimental designs are more likely to have problems with internal validity because of how they recruit participants, whereas observational designs do not suffer from this difficulty as often

What is the most significant benefit of randomly assigning participants to different treatment groups?

• It ensures that you have a credible causal mechanism linking X to Y.

• It ensures that the sample is an accurate representation of the population at large

• It controls for other possible causes of the dependent variable.

• Both (a) and (b).

Which of the following is a potential drawback of the experimental research design?

• Not every independent variable is subject to experimental manipulation.

• Experiments often suffer from low degrees of external validity.

• Some experimental situations create ethical dilemmas for researchers

• all of the above

Which of the following causal hurdles is more difficult to cross in experimental than observational research?

• Is there a credible causal mechanism linking X to Y ?

• Could Y cause X?

• Is there covariation between X and Y?

• None of the above

True or false a measurement must be both valid and reliable to be useful in hypothesis testing?

• True

• False, only reliability is essential for conducting hypothesis tests.

• False, only validity is essential for conducting hypothesis tests.

• False, a measure must be either valid or reliable, but it need not be both.

Among the following imperfect measures which one is nevertheless potentially useful for purposes of hypothesis testing?

• A reliable but invalid measure.

• A measurement systematically biased in one direction but still a reliable measure

• An invalid but reliable measure.

• None of the above.

If a measure of a concept is correlated with a measure of another concept in the way the theory predicts then the measure of the concept is said to possess which of the following characteristics?

• Face validity.

• Content validity.

• Construct validity

• Both (b) and (c).

What is Content validity?

• The degree to which a measure contains all of the critical elements that as a group define the concept we wish to measure.

• The degree to which a measure does not contains all of the critical elements that as a group define the concept we wish to measure.