1. A researcher decides to com
1.
A researcher decides to compare three groups of subjects on adecision-making task, to see if people make riskier decisions whentheir friends were around. She compares three groups, either withtheir friends present, absent, or a stranger nearby. She conducts aone-way between-subjects ANOVA and obtains the following values forher F-table
Source of Error | SS | df | MS | F |
BG | 2024 | 2 | 1012 | 3.42 |
Error | 5328 | 18 | 296 | |
Total | 14712 | 20 |
2.
A researcher is interested in studying if different methods forcommuting lead to greater happiness. He tests three groups:drivers, train riders, and bike riders. Each group completes ahappiness questionnaire, with higher values indicating greaterhappiness. She collects the following data.
Drivers |
Train Riders |
Bike Riders |
5 |
17 |
92 |
7 |
17 |
24 |
13 |
33 |
52 |
41 |
55 |
60 |
28 |
47 |
60 |
59 |
74 |
94 |
37 |
57 |
72 |
Calculate the test statistic (F-obtained) for this statisticaltest (One-way Between Subjects ANOVA)
Answer:
1. A researcher decides to compare three groups of subjects on adecision-making task, to see if people make riskier decisions whentheir friends were around. She compares three groups, either withtheir friends present, absent, or a stranger nearby. She conducts aone-way between-subjects ANOVA and obtains the following values forher F-table
Here we have to test the hypothesis that,
H0 : people do not make riskier decisions when their friendswere around.
H1 : people make riskier decisions when their friends werearound.
Assume alpha = level of significance = 0.05
Test statistic F = 3.42
Now we have to find P-value for taking decision.
We can find P-value in excel.
syntax :
=FDIST(x, deg_freedom1, deg_freedom2)
where x is test statistic
deg_freedom1 = 2
deg_freedom2 = 18
P-value = 0.0551
P-value > alpha
Accept H0 at 5% level of significance.
Conclusion : People do not make riskier decisions when theirfriends were around.
Three groups population means are same.
2. A researcher is interested in studying if different methodsfor commuting lead to greater happiness. He tests three groups:drivers, train riders, and bike riders. Each group completes ahappiness questionnaire, with higher values indicating greaterhappiness. She collects the following data.
This is also one way anova.
We can do one way anova in excel.
syntax :
ENTER data into excel sheet –> Data –> Data analysis–> Anova : single factor –> Ok –> Input range : selectall the data together –> Labels in first row –> Alpha :0.05 –> Output range : select one empty cell–> ok
Test statistic F= 5.20