Do a two-sample test for equality of means assuming unequal variances. Calculate the p-value using Excel. (a-1) Comparison of GPA for randomly chosen college juniors and seniors: x⎯⎯1 = 4, s1 = .20, n1 = 15, x⎯⎯2 = 4.25, s2 = .30, n2 = 15, α = .025, left-tailed test. (Negative values should be indicated by a minus sign. Round down your d.f. answer to the nearest whole number and other answers to 4 decimal places. Do not use "quick" rules for degrees of freedom.) d.f. t-calculated p-value .0088 t-critical -2.145 (a-2) Based on the above data choose the correct decision. Reject the null hypothesis Do not reject the null hypothesis (b-1) Comparison of average commute miles for randomly chosen students at two community colleges: x⎯⎯1 = 17, s1 = 5, n1 = 22, x⎯⎯2 = 21, s2 = 7, n2 = 19, α = .05, two-tailed test. (Negative values should be indicated by a minus sign. Round down your d.f. answer to the nearest whole number and other answers to 4 decimal places. Do not use "quick" rules for degrees of freedom.) d.f. t-calculated p-value t-critical +/- (b-2) Based on the above data choose the correct decision. Do not reject the null hypothesis Reject the null hypothesis (c-1) Comparison of credits at time of graduation for randomly chosen accounting and economics students: x⎯⎯1 = 141, s1 = 2.8, n1 = 12, x⎯⎯2 = 138, s2 = 2.7, n2 = 17, α = .05, right-tailed test. (Negative values should be indicated by a minus sign. Round down your d.f. answer to the nearest whole number and other answers to 4 decimal places. Do not use "quick" rules for degrees of freedom.) d.f. t-calculated p-value t-critical (c-2) Based on the above data choose the correct decision. Reject the null hypothesis Do not reject the null hypothesis
Sol:
Part a)
Test Statistic :-
t = -3.2225
Test Criteria :-
Reject null hypothesis if t < -t(α, DF)
DF = 24
Critical value t(α, DF) = t( 0.025 , 24 ) =
2.064
t < -t(α, DF) = -3.2225 < -2.064
Result :- Reject Null Hypothesis
Decision based on P value
P - value = P ( t > 3.2225 ) = 0.0018
Reject null hypothesis if P value < α level of
significance
P - value = 0.0018 < 0.025 ,hence we reject null
hypothesis
Conclusion :- Reject null hypothesis
Part b)
Test Statistic :-
t = -3.1128
Test Criteria :-
Reject null hypothesis if | t | > t(α/2, DF)
DF = 32
Critical value t(α/2, DF) = t(0.05 /2, 32 ) = 2.037
| t | > t(α/2, DF) = 3.1128 > 2.037
Result :- Reject Null Hypothesis
Decision based on P value
P - value = P ( t > 3.1128 ) = 0.0039
Reject null hypothesis if P value < α = 0.05 level of
significance
P - value = 0.0039 < 0.05 ,hence we reject null hypothesis
Conclusion :- Reject null hypothesis
Part c)
Test Statistic :-
t = 0.9613
Test Criteria :-
Reject null hypothesis if t > t(α, DF)
DF = 23
Critical value t(α, DF) = t( 0.05 , 23 ) =
1.714
t > t(α, DF) = 0.9613 < 1.714
Result :- Fail to Reject Null Hypothesis
Decision based on P value
P - value = P ( t > 0.9613 ) = 0.1732
Reject null hypothesis if P value < α level of
significance
P - value = 0.1732 > 0.05 ,hence we fail to reject null
hypothesis
Conclusion :- We Accept H0
Do a two-sample test for equality of means assuming unequal variances. Calculate the p-value using Excel....
Do a two-sample test for equality of means assuming unequal variances. Calculate the p-value using Excel. (a-1) Comparison of GPA for randomly chosen college juniors and seniors: x⎯⎯1x1 = 4.75, s1 = .20, n1 = 15, x⎯⎯2x2 = 5.18, s2 = .30, n2 = 15, α = .025, left-tailed test. (Negative values should be indicated by a minus sign. Round down your d.f. answer to the nearest whole number and other answers to 4 decimal places. Do not use "quick"...
Do a two-sample test for equality of means assuming unequal variances. Calculate the p-value using Excel. (a-1) Comparison of GPA for randomly chosen college juniors and seniors: x⎯⎯1x1 = 4.75, s1 = .20, n1 = 15, x⎯⎯2x2 = 5.18, s2 = .30, n2 = 15, α = .025, left-tailed test. (Negative values should be indicated by a minus sign. Round down your d.f. answer to the nearest whole number and other answers to 4 decimal places. Do not use "quick"...
Do a two-sample test for equality of means assuming unequal variances. Calculate the p-value using Excel. (a-1) Comparison of GPA for randomly chosen college juniors and seniors: x⎯⎯1x1 = 4.75, s1 = .20, n1 = 15, x⎯⎯2x2 = 5.18, s2 = .30, n2 = 15, α = .025, left-tailed test. (Negative values should be indicated by a minus sign. Round down your d.f. answer to the nearest whole number and other answers to 4 decimal places. Do not use "quick"...
Do a two-sample test for equality of means assuming unequal variances. Calculate the p-value using Excel. (a-1) Comparison of GPA for randomly chosen college juniors and seniors: x⎯⎯1 = 4, s1 = .20, n1 = 15, x⎯⎯2 = 4.25, s2 = .30, n2 = 15, α = .025, left-tailed test. (Negative values should be indicated by a minus sign. Round down your d.f. answer to the nearest whole number and other answers to 4 decimal places. Do not use "quick"...
Do a two-sample test for equality of means assuming unequal variances. Calculate the p-value using Excel. (a-1) Comparison of GPA for randomly chosen college juniors and seniors: x⎯⎯1 = 4, s1 = .20, n1 = 15, x⎯⎯2 = 4.25, s2 = .30, n2 = 15, α = .025, left-tailed test. (Negative values should be indicated by a minus sign. Round down your d.f. answer to the nearest whole number and other answers to 4 decimal places. Do not use "quick"...
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