Shapiro-Wilk p-value is 0.0072, W = 0.8844. Data Points 26. Table data for W: n = 26, W = 0,891 - a = 0,0,1; W = 0,92 - a = 0,05. Is distribution normal in my case?
With almost certainty: it is not normal (unless it is a synthetic variable, and even then it ay be doubtful, depending on the RNG used).
Note 1: the test cannot give any indication or evidence for the assumption that the tested distribution is normal. It only checks if the given sample size is already sufficient to reject this hypothesis. Failing to reject only means that the sample size is too small.
Note 2: I bet that answering the question "are my data sampled from a normal distribution?" is not what you need. I guess that the correctly formulated question is rather: "are my data sampled from a distribution that is sufficiently similar to a normal distribution to warrant conclusions from analysis methods assuming that the data are samples from a normal distribution?". This is a considerably different question, and this cannot be answered by "Normality test" like Shapiro-Wilk etc.
You need to go back to the method used and check the required values to judge the data if it is normally distributed or not!!. Regards.
Referring to Jochen Wilhelm Note 2, if the question is "are my data sampled from a distribution that is sufficiently similar to a normal distribution to warrant conclusions from analysis methods assuming that the data are samples from a normal distribution?" I think the attached paper could be of use...
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