Question

Q1 A researcher recorded the scores of 20 students in a written examination, trained in different methods, as shown below.

The data is arranged according to the training method used

TRAINING METHOD SCORES

Video Cassette 74 88 82 93 55 70

Audio Cassette 78 80 65 57 89

Classroom 68 83 50 91 84 77 94 81 92

1. Formulate and test the hypotheses to determine whether the examination scores among the 3 methods above are significantly different at 5% significance level

B Assume that you are carrying out a research at a university with 2000 students. How large a sample should you get to estimate the proportion of students who smoke to within a margin of error of ±5%, using any formulae. 10 marks

Answer 1

Anova: Single Factor
SUMMARY
Groups	Count	Sum	Average	Variance
Video Cassette	6	462	77	188.8
Audio Cassette	5	369	73.8	161.7
Classroom	9	720	80	192.5
ANOVA
Source of Variation	SS	df	MS	F	P-value	F crit
Between Groups	126.15	2	63.075	0.342492	0.714786	3.591531
Within Groups	3130.8	17	184.1647
Total	3256.95	19

Since P-value=0.714786>0.05 so we fail to reject H₀ at 5% level of significance and there is insufficient evidence to conclude that the examination scores among the 3 methods are significantly different at 5% significance level.

B.