Why do educational researchers usually use the .05 level of significance?
According to the electronic textbook StatSoft, "one could
say that the statistical significance of a result tells us
something about the degree to which the result is "true" (in the
sense of being "representative of the population"). More
technically, the value of the p-value represents a decreasing index
of the reliability of a result." A 0.05 level significance is the
standard margin of error recognized in most areas of reseachers,
meaning that probability of error that is involved for most
reseachers is 5% their results.
StatSoft. (1984-2008). Elementary concepts in statistics.
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