2. T-test for independent samples
The t-test is a test difference between two independent
groups. The means are compared Mean 1 against the Mean
2.
When do we use the t-test for independent samples?
When we compare the means of two independent groups.
When the data are expressed in interval and ratio.
When the sample is less than 30.
3.
4.
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7.
8.
9.
10.
11. F-Test
The F-test (ANOVA- Analysis of Variance) is
another parametric test used to compare the means
of three or more groups of independent samples.
Why do we use F-test?
Because we want to find out if there is a significant
difference between and among the means of three or
more independent groups.
12.
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24. Exercise
In an experiment to determine the germicidal effect of 3 brands of bath
soap, 5 groups of nursing students were randomly assigned to each of
the 3 popular brands of soap: Brand A, B, and C. Bacterial count after
1 hour of using the soap was recorded as shown in table1. Find if
there’s a significant difference (5% level) among the different brands
of soap using ANOVA.
BRAND
A
8
7
9
13
10
B
14
16
12
17
11
C
10
12
16
15
12
