Here's a short video with footage from an experiment that tested dogs' empathy. Watch the video with these questions in mind.
a) The study was an experiment. What was the independent variable (IV)?
b) Was the IV manipulated as between-groups (independent groups) or within-groups? What keywords in the video description helped you answer this question?
c) The dependent variable (DV) was operationalized in two ways. What were they?
d) One of the DVs did not support the hypothesis, but the other DV did. Explain the results that they found. (You can sketch two little bar graphs, too.)
e) What do you think--does "opening a door to release a crying owner" indicate "empathy?" (P.S., That's a construct validity question.)
f) Does the study support the claim that "hearing their owners ask for help while crying causes dogs to help their owners faster"? Apply the three causal criteria to support your answer.
a) The IV was whether the owners were saying "help" while pretending to cry, or saying "help" in a neutral tone, while humming Twinkle Twinkle Little Star.
b) This was independent-groups--the reporter used keywords such as "some owners" and "other owners". This was a posttest-only design.
c) One operationalization of the DV was whether the dogs opened the door, or not. The other operationalization of the DV was how long each dog took to open the door.
d) Only the "time taken" DV showed the predicted effect.
e) Answers will vary
f) The results show covariance because dogs whose owners were crying opened the door three times as fast as dogs whose owners were calm. Temporal precedence is ensured by the methodology--by randomly assigning owners to cry (vs. sing), they ensured that this condition came before opening the door. The study would have good internal validity if they randomly assigned owner/dog pairs to the two conditions--this would take care of selection threats such as having more "already helpful" dogs in the crying condition, or having owners who are better at acting in one condition or the other. As far as design confounds, we might ask about whether the owners in the two conditions acted exactly the same in all ways except their assigned conditions.