Appendix I

Appendix I: Results from Analyzing the Collection of Primary Data

Table1. Difference of Means Tests: Treatment Versus Control, standard deviations in parentheses under means and 2-tailed significance tests in parentheses under t-tests

	Pretest Mean		Independent Samples t-test	Mean Difference	Posttest Mean		Independent Samples t-test	Mean Difference	N
	Trtmt	Control			Trtmt	Control
Entire Sample	64.9128 (12.11)	62.554 (12.57)	1.101 (0.273)	2.359	78.706 (6.08)	74.981 (9.17)	2.792* (0.006)	3.725	133
Sem 1	60.533 (10.71)	56.970 (13.96)	0.988 (0.328)	3.564	79.914 (5.87)	74.221 (9.02)	2.594* (0.013)	5.694	47
Sem 2	63.442 (13.66)	65.422 (10.09)	-0.547 (0.587)	-1.981	75.996 (6.19)	75.768 (8.44)	0.102 (0.919)	0.227	44
Sem 3	70.823 (9.86)	65.873 (11.73)	1.485 (0.145)	4.950	79.931 (5.60)	74.947 (10.56)	1.977* (0.055)	4.984	42

Table 2: Ordinary Least Squares Regression Results, Dependent Variable: Posttest t-statistics are in parentheses.

Coefficient

Entire Sample

Semester 1

Semester 2

Semester 3

Treatment

3.234
(2.24)

4.778

(1.68)

-0.382

(-0.14)

4.649

(1.67)

Fall

-0.986

(-0.63)

n.a.

Sex

-0.539

(-0.40)

1.619

(0.83)

0.619

(0.21)

4.352

(4.57)

Age

0.307

(1.67)

-0.057

(-0.25)

0.351

(1.31)

1.307

(3.84)

NonCBA

-0.977

(-0.58)

2.116

(0.60)

-1.368

(-0.41)

3.307

(1.08)

Econmajor

3.648

(2.07)

2.321

(0.64)

1.357

(0.42)

5.680

(2.33)

CumGPA

2.511

(1.28)

4.882

(1.83)

2.411

(0.76)

3.319

(1.17)

Grade

-1.876

(-1.32)

-2.989

(-0.94)

-1.103

(-0.48)

3.896

(1.74)

ACTEng

-0.643

(-2.00)

-0.985

(-1.66)

-1.282

(-1.58)

0.937

(1.43)

ACTMth

-0.374

(-1.28)

-0.399

(-0.92)

-1.495

(-2.81)

0.723

(1.36)

ACTComp

1.030

(2.02)

1.272

(1.53)

2.953

(2.48)

1.461

(1.57)

Elective

-0.764

(-0.20)

n.a.

1.234

(0.46)

3.512

(0.31)

Required

-0.674

(-0.44)

1.099

(0.30)

0.370

(0.12)

1.649

(0.65)

Constant

66.712

(10.55)

69.979

(7.49)

61.085

(6.72)

46.519

(4.08)

R-Squared

0.1625

0.2628

0.2645

0.4416

133

Source: author’s calculations.