Research Scenario #2:
A researcher wanted to study the effect of alcohol on reaction time. She hypothesized that alcohol will INCREASE reaction time (participants will take longer to react). She selected a sample of n= 36 participants from Rutgers University. The 36 participants each consumed a 6-ounce glass of wine. Thirty minutes later, the researcher measured each participant’s reaction time, using a standardized driving simulation task for which the regular population has a µ = 400 msec reaction time with a σ = 48. The reaction time mean for the sample was M= 412 msec. Are the data sufficient to conclude that the alcohol significantly increased reaction time?
Based on the above research scenario, please answer the following questions:
Step 1:
Step 2:
Step 3:
Step 4: _______________________________
Write the statistical statement for the results: __________________________________
Interpret your results (relating back to the hypothesis): _______________________________________________________________________________________________________________________________________________________________________________________________________________________________________
If appropriate, please compute effect size: Answer: _______
Ans:
One sample mean test(z test)
We are comparing sample mean to a hypothised mean value of 400.
alpha=0.05
critical z value=1.645
Decision rule:Reject H0,if z>1.645
Test statistic:
z=(412-400)/(48/sqrt(36))
z=1.5
p-value=P(z>1.5)=0.0668
As,p-value>0.05,we fail to reject the null hypothesis.
There is not sufficient evidence to conclude that the alcohol significantly increased reaction time.
Effect size=(412-400)/48=0.25
Research Scenario #2: A researcher wanted to study the effect of alcohol on reaction time. She...
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