Quiz 6.

To investigate if online tutoring is as effective (measured by passing rate) as tutoring in person, we collected random samples of students using each of the tutoring method exclusively and performed two statistical analysis (Chi square and correlation). In the outputs, tutor=1 means online, tutor=0 in person, pass =1 means passed a course while 0 means failed. Choose the correct method and report your findings.

Output1 Pearson Correlation Coefficients,Prob > |r| under H0: Rho=0

tutoring pass

tutoring 1.00000 0.47579

0.0642

pass 0.47579 1.00000

0.0642

Output2

pass tutor

Frequency

Percent

Row Pct

Col Pct 0 1 Total

0 60 30 90

12.24 6.12 18.37

66.67 33.33

21.43 14.29

1 220 180 400

44.90 36.73 81.63

55.00 45.00

78.57 85.71

Total 280 210 490

57.14 42.86 100.00

Statistics for Table of pass by tutor

Statistic DF Value Prob

Chi-Square 1 4.2833 0.0244

Likelihood Ratio Chi-Square 1 4.1663 0.0412

Continuity Adj. Chi-Square 1 3.6208 0.0571

Mantel-Haenszel Chi-Square 1 4.0750 0.0435