difference testing. p > .05 indicates what? when a person concludes that there is a difference between population means when she has actually observed an improbable difference between two sample means that come from identical populations, she has made what type of error? findings are said to be statistically significant when there is a ???? probability that differences among treatment groups were caused by chance factors. the probability that a specific result will occur strictly as a result of chance is called what? an anova yields what type of test statistic? what are the components of this statistic? which statistical technique tests for significant differences between observed and expected frequencies of occurrence?