I have the following 2 samplesdata 1 : 59.09 59.17 59.27 59.13 59.10 59.14 59.54 59.90data 2: 59.06 59.40 59.00 59.12 59.01 59.25 59.23 59.564And I need to check whether there is differentiation regarding the mean and the variance between the 2 data samples at significance level a=0.05I think that the first thing I need to do is to check whether the samples come from a normal distribution in order to infer whether i should proceed using parametric or non marametric tests...However using lillietest in matlab returned that both samples do not follow the normal distribution...Any ideas on how should I proceed with checking the differentiation tests ? Should I perform ttest ? Or should I proceed by using something like Wilcoxon ? (p.s please confirm that that both data samples do not follow normal distribution...)

Question

I have the following 2 samplesdata 1 : 59.09  59.17   59.27   59.13   59.10   59.14   59.54   59.90data 2:  59.06  59.40   59.00   59.12   59.01   59.25   59.23   59.564And I need to check whether there is differentiation regarding the mean and the variance between the 2 data samples at significance level a=0.05I think that the first thing I need to do is to check whether the samples come from a normal distribution in order to infer whether i should proceed using parametric or non marametric tests...However using lillietest in matlab returned that both samples do not follow the normal distribution...Any ideas on how should I proceed with checking the differentiation tests ? Should I perform ttest ? Or should I proceed by using something like Wilcoxon ? (p.s please confirm that that both data samples do not follow normal distribution...)

Raiden Williamson · Accepted Answer

For a t-test, you need the samples to follow a normal distribution, so you&#039;re right to check this assumption first. I did a Shapiro-Wilk to test the normality, and it is rejected for the first sample, but it is not for the second sample. Thus you can&#039;t use a t-test.The alternative is to use the Wilcoxon test, which is non-parametric.Here is the code I have used with R :data1 &amp;lt;- c(59.09, 59.17, 59.27, 59.13, 59.1, 59.14, 59.54, 59.9)data2 &amp;lt;- c(59.06, 59.4, 59, 59.12, 59.01, 59.25, 59.23, 59.564)shapiro.test(data1)# P-value = 0.007987. Normality is rejected.shapiro.test(data2)# P-value = 0.3873. Normality is not rejected.wilcox.test(data1, data2)# P-value = 0.5054. No significative difference.

I have the following 2 samples data 1 : 59.09 59.17 59.27 59.13 59.10 59.14 59.54 59.

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