PRE-TEST POST-TEST t-Test: Paired Two Sample for Means 6 10 5 7 PRE-TEST POST-TEST 7 12 Mean 5.928571429 9.5 10 12 Variance 4.532967033 3.038461538 8 10 Observations 14 14 5 8 Pearson Correlation 0.404178406 5 10 Hypothesized Mean Difference 0 7 8 df 13 8 12 t Stat -6.25 7 9 P(T<=t) one-tail 1.48588E-05 4 8 t Critical one-tail 1.770933396 6 7 P(T<=t) two-tail 2.97177E-05 3 10 t Critical two-tail 2.160368656 2 10 Plain PRE-TEST POST-TEST t-Test: Paired Two Sample for Means 5 9 4 8 PRE-TEST POST-TEST 3 5 Mean 5.642857143 7.428571429 9 8 Variance 3.631868132 7.648351648 7 5 Observations 14 14 7 6 Pearson Correlation 0.337772791 5 12 Hypothesized Mean Difference 0 6 8 df 13 7 7 t Stat -2.404769875 2 5 P(T<=t) one-tail 0.015899882 8 14 t Critical one-tail 1.770933396 6 5 P(T<=t) two-tail 0.031799765 5 7 t Critical two-tail 2.160368656 5 5 STYLIZED PLAIN t-Test: Paired Two Sample for Means 10 9 7 8 STYLIZED PLAIN 12 5 Mean 9.5 7.428571429 p s 12 8 Variance 3.038461538 7.648351648 2.77 1.74 10 5 Observations 14 14 8 6 Pearson Correlation -0.127654415 10 12 Hypothesized Mean Difference 0 8 8 df 13 12 7 t Stat 2.25 9 5 P(T<=t) one-tail 0.02139551 8 14 t Critical one-tail 1.770933396 7 5 P(T<=t) two-tail 0.04279102 10 7 t Critical two-tail 2.160368656 10 5 STYLIZED PLAIN t-Test: Paired Two Sample for Means 4.00 3.71 3.71 3.71 STYLIZED PLAIN 3.86 3.14 Mean 3.78 3.69 p s 3.86 3.71 Variance 0.077595874 0.103162144 0.32 0.28 3.29 3.71 Observations 14 14 3.57 3.86 Pearson Correlation -0.17796778 4.00 3.86 Hypothesized Mean Difference 0 3.14 3.86 df 13 4.00 3.86 t Stat 0.66 4.00 4.00 P(T<=t) one-tail 0.26 3.71 3.57 t Critical one-tail 1.770933396 3.71 4.00 P(T<=t) two-tail 0.519265236 4.00 2.86 t Critical two-tail 2.160368656 4.00 3.86
Added by Lacap, L.
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This test compares the means of two related groups to determine whether there is a statistically significant difference between these means. The data includes pre-test and post-test scores for different groups. Show more…
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t-Test: Paired Two Sample for Means Variable 1 Variable 2 Mean 38 43.3 Variance 52.44444 149.3444 Observations 10 10 Pearson Correlation 0.728184 Hypothesized Mean Difference 0 df 9 t Stat -1.96296 P(T<=t) one-tail 0.040628 t Critical one-tail 1.833113 P(T<=t) two-tail 0.081256 t Critical two-tail 2.262157 which is the p-value on this table
Aparna S.
Consider the following data from a repeated-measures design. You want to use a repeated-measures t-test to test the null hypothesis H₀: μD = 0 (the null hypothesis states that the mean difference for the general population is zero). The data consist of five observations, each with two measurements, A and B, taken before and after a treatment. Assume the population of the differences in these measurements are normally distributed. Complete the following table by calculating the differences and the squared differences: Observation A B Difference Score Squared Difference Score (D = B – A) (D²) 1 1 2 1 1 2 2 3 1 1 3 3 4 1 1 4 6 4 -2 4 5 5 6 1 1 6 8 5 -3 9 The mean difference score is MD = -0.5. For a repeated-measures t-test, you need to calculate the t statistic, which requires you to calculate s and sMD. What is the estimated standard deviation of the difference scores? s = √(ΣD² / n - 1) = √(17 / 5) = 1.30 What is the estimated standard error of the mean difference scores? (Note: For best results, retain at least six decimal places from your calculation of s.) sMD = s / √n = 1.30 / √6 = 0.581 What is the t statistic for the repeated-measures t-test to test the null hypothesis H₀: μD = 0? t = MD / sMD = -0.5 / 0.581 = -0.861 t Distribution Degrees of Freedom = 5 You conduct a two-tailed test at α = .05. To use the Distributions tool to find the critical values, you first need to set the degrees of freedom in the tool. The degrees of freedom are 5. The critical values (the values for t scores that separate the tails from the main body of the distribution, forming the critical region) are -2.571 and 2.571. Finally, since the t statistic -0.861 is not in the critical region, you fail to reject the null hypothesis.
Sri K.
t-Test: Two-Sample Assuming Equal Variances ADKAR PROSCI Mean 5.61 7.326666667 Variance 4.798172414 1.855816092 Observations 30 30 Pooled Variance 3.326994253 Hypothesized Mean Difference 0 df 58 t Stat -3.645067529 P(T<=t) one-tail 0.000286392 t Critical one-tail 1.671552762 P(T<=t) two-tail 0.000572783 t Critical two-tail 2.001717484 Significance level: 0.05 How do I determine the characteristics of the comparison distribution?
Adi S.
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