Case Study

Based on the manipulation check, how should the researcher interpret the null result? Justify your conclusion using the principles of manipulation checks.

Case context: A researcher attempts to put participants into a state of high anxiety by telling them they will give a public speech, intending to see if anxiety reduces cognitive test scores. The test scores between the speech group and a control group show no difference (a null result). A manipulation check asking participants to rate their anxiety levels reveals that the speech group did not feel any more anxious than the control group.

Question: Based on the manipulation check, how should the researcher interpret the null result? Justify your conclusion using the principles of manipulation checks.

Sample answer: Because the manipulation check showed no change in anxiety between the groups, the manipulation failed to alter the participants' state. Therefore, the researcher cannot conclude that anxiety has no effect on test scores; rather, the true relationship between anxiety and cognitive test scores remains unknown.

Key points:

  • Identify that the manipulation check showed no change in the participants' actual state.
  • Conclude that the manipulation itself failed to induce anxiety.
  • State that the true relationship between anxiety and test scores remains unknown.
  • Avoid concluding that anxiety has no effect on cognitive test scores.

Rubric: The answer must explicitly state that the manipulation failed and correctly conclude that the true relationship between the independent and dependent variables remains unknown.

0

1

Updated 2026-05-27

Contributors are:

Who are from:

Tags

KPU

Research Methods in Psychology - 4th American Edition @ KPU

Related