I have the following data on duration that different aged adults can remain standing. <mtable c

sebadillab0 2022-07-07 Answered
I have the following data on duration that different aged adults can remain standing.
 Age   Sample Size   Sample Mean   Sample Std Dev   Old  28 801 117  Young  16 780 72
The data I'm using has a normal distribution with the same variances. I want to do a test of hypotheses however at a significance level of 5% (a=0.05) to be able to confirm whether or not the average duration that older adults can remain standing is larger than among younger adults.

I'm not sure which of the different formulas I should use however to determine this due to my sample size being relatively small. Should I be using the following test.

to compute pooled standard deviation: s 2 = ( 1 1 ) s 1 2 + ( n 2 1 ) s 2 2 n 1 + n 2 2

compute test statistics: t = y 1 y 2 0 s 1 n 1 + 1 n 2
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Answers (1)

bap1287dg
Answered 2022-07-08 Author has 13 answers
In the statement of the problem, you claim that the data have a normal distribution with the same variance. If that's the case, then you should indeed perform a two sample t-test assuming equal variances. The sample size being small is not an issue since you are told the data are normal. Also, since you are told that the variances are the same, you are correct to calculate the pooled standard deviation.
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