After careful ethical review of planned procedures, a researcher tests a new brain activation drug by taking a sample of 50 volunteers and randomly assigning 25 participants to the treatment condition and 25 to the control (placebo)condition.She then carries out an fMRI scan to assess the level of activation in regions of the participants' brains 30 minutes after administering the drug.She carries out a between-participants t-test in SPSS which provides the output shown below: Which of the following statements is true?
A)The assumption of equal variance is irrelevant.
B)The assumption of equal variance is violated.
C)The assumption of equal variance might be violated but we cannot tell from this output as we only have standard deviations
D)We cannot judge whether the assumption of equal variances is violated as we need to see the population distribution.
E)None of the above.

Question

After careful ethical review of planned procedures, a researcher tests a new brain activation drug by taking a sample of 50 volunteers and randomly assigning 25 participants to the treatment condition and 25 to the control (placebo)condition.She then carries out an fMRI scan to assess the level of activation in regions of the participants' brains 30 minutes after administering the drug.She carries out a between-participants t-test in SPSS which provides the output shown below:  Which of the following statements is true?
A)The assumption of equal variance is irrelevant. 
B)The assumption of equal variance is violated. 
C)The assumption of equal variance might be violated but we cannot tell from this output as we only have standard deviations 
D)We cannot judge whether the assumption of equal variances is violated as we need to see the population distribution. 
E)None of the above.

Quizplus · Accepted Answer

The Answer of After careful ethical review of planned procedures, a researcher tests a new brain activation drug by taking a sample of 50 volunteers and randomly assigning 25 participants to the treatment condition and 25 to the control (placebo)condition.She then carries out an fMRI scan to assess the level of activation in regions of the participants' brains 30 minutes after administering the drug.She carries out a between-participants t-test in SPSS which provides the output shown below:  Which of the following statements is true?
A)The assumption of equal variance is irrelevant. 
B)The assumption of equal variance is violated. 
C)The assumption of equal variance might be violated but we cannot tell from this output as we only have standard deviations 
D)We cannot judge whether the assumption of equal variances is violated as we need to see the population distribution. 
E)None of the above.

After Careful Ethical Review of Planned Procedures, a Researcher Tests