Question

A academic helper wants to assess whether her remedial tutoring has been effective for her five students. She decides to conduct a related samples t-test and records the following grades for students prior to and after receiving her tutoring.

Tutoring
Before	After
2.4	3.0
2.5	2.8
3.0	3.6
2.9	3.2
2.7	3.5

(a) Test whether or not her tutoring is effective at a 0.05 level of significance. State the value of the test statistic. (Round your answer to three decimal places.)
t =

State the decision to retain or reject the null hypothesis.

Retain the null hypothesis. Reject the null hypothesis.

(b) Compute effect size using estimated Cohen's d. (Round your answer to two decimal places.)
d =

Answer 1

Tutoring "After Before 2.4 3.0 2.5 2.8 X = 2.7 J = 3.22 S = 0.065 S₂ r.= 0.112 3.0 3.6 2.9 3.2 1,0225 2.7 3.5 grade resoroton of 2 Let x be a random variable denotes the students before Tutoring. and let E(X) = M and vcx) = 62 y be a random variable after tutoring, ECY) = 1 denohes grade of atud and V(Y) = 62% Here our testing problem is Hoo Mis ų vs. His My CM SVI t. Test statistic to ² sor where sr (1,-1) Sint (M21) S22 Ntni tl₂-2 n, th₂-2 S = Sample Standard deviation before tutoring Sir Sample sod afte to Antoning We reject the null hypothesis di non 71-7 if - final t C-ta, n, th2=2

(n-1) S +n₂-1) S. 2 n+n₂-2 4(0.065+0.112) 5+5-2 = 0.0885 5 0.297 Now, 4 2.7 -3.22 F stata 0.297 - - 2.768 For 220.05 to.os, 8 = 1.860 Here t <- to.os, 8 , so we can say that effective, ie we reject the null hypothesis. tutoring en (6) coherde (X-71 S 3.22 - 2.7 0.297 - 1.75