The above result shows that there is a significant difference in the values of both the ROE figures
of the bank i.e before the introduction of the act and after the introduction of the act. It is evident
from the fact that T stat value is greater than T critical value for two tail. Also the t stat value is
higher than t critical value so we accept the Null hypothesis.
i.e the ROE would be lower following the enactment of the Sarbanes-Oxley Act.

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t-Test: Two-Sample Assuming Equal Variances
For alpha
=0.05
Before SOX
After SOX
Mean
30.632
21.422
Variance
811.682627
4
307.292532
6
Observations
20
20
Pooled Variance
559.48758
Hypothesized Mean Difference
0
df
38
t Stat
1.23130149
P(T<=t) one-tail
0.11288820
8
t Critical one-tail
1.68595446
P(T<=t) two-tail
0.22577641
5
t Critical two-tail
2.02439416
4
Compare the t-critical value in the output with the t-value. The t-value (1.231) is smaller than the
t-critical value (2.024). Therefore we accept the null hypothesis. i.e there is significance
difference between the ROE's before and after the introduction of SOX.
The above result shows that there is a significant difference in the values of both the ROE figures
of the bank i.e before the introduction of the act and after the introduction of the act. It is evident
from the fact that T stat value is greater than T critical value for two tail. Also the t stat value is
higher than t critical value so we accept the Null hypothesis.
i.e the ROE would be lower following the enactment of the Sarbanes-Oxley Act.

t-Test: Two-Sample Assuming Equal Variances
For alpha
=0.10
Before SOX
After SOX
Mean
30.632
21.422
Variance
811.682627
4
307.292532
6
Observations
20
20
Pooled Variance
559.48758
Hypothesized Mean Difference
0
df
38
t Stat
1.23130149
P(T<=t) one-tail
0.11288820
8
t Critical one-tail
1.30423020
4
P(T<=t) two-tail
0.22577641
5
t Critical two-tail
1.68595446
Compare the t-critical value in the output with the t-value. The t-value (1.231) is smaller than the
t-critical value (1.686). Therefore we accept the null hypothesis. i.e there is significance
difference between the ROE's before and after the introduction of SOX.
For
Alpha
1%
t Critical Value
2.712
For
Alpha
5%
t Critical Value
2.024
For
Alpha
10%
t Critical Value
1.686
It is clearly evident that if we go on increasing the significance level, the acceptability range goes
on decreasing.

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- Winter '18