Question

2. An experiment in teaching introductory biology was conducted at a large university. One section was taught by the traditional lecture-lab method, a second was taught by an all lab/demonstration approach with no lectures, a third was taught entirely by a series of videotaped lectures and demonstrations that students were free to view at any time and as often as they wanted. Students were randomly assigned to each of the three sections and, at the end of the semester, random samples of final exam scores were collected from each section. Use the five-step model to determine if there is a significant difference in student performance by teaching method. Test at α=.05. How much of the variation in student performance can be explained by the teaching method?

Lecture	Demonstration	Videotape
55	56	50
57	60	52
60	62	60
63	67	61
72	70	63
73	71	69
79	82	71
85	88	80
92	95	82

Answer 1

using excel data analysis tool for one factor anova, following o/p Is obtained,

Anova: Single Factor
SUMMARY
Groups	Count	Sum	Average	Variance
Lecture	9	636	70.66667	167.75
Demonstration	9	651	72.33333	176.75
Videotape	9	588	65.33	125.50
ANOVA
Source of Variation	SS	df	MS	F	P-value	F crit
Between Groups	240.667	2	120.333	0.768	0.475	3.403
Within Groups	3760.00	24	156.667
Total	4000.67	26

step 1).

Ho: there is no significant difference in student performance by teaching method

H1:there is a significant difference in student performance by teaching method

step 2

F-stat=0.768

step 3

p-value =0.475

step 4)

since, p-value >α=0.05, fail to reject Ho

step 5)

there is not enough evidence to conclude that there is a significant difference in student performance by teaching method at α=0.05

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variation in student performance can be explained by the teaching method = SS between / SS total = 240.667/4000.67 = 0.0602

so, 6.02% of variation in student performance can be explained by the teaching method