Z test is applied for large samples. Z test = (Estimated Mean – Real Mean)/ (square root real variance / n).
Chi-Square test is a statistical method assessing the goodness of fit between a set of observed values and those expected theoretically.
F-test is used to compare 2 populations’ variances. F = explained variance/unexplained variance.
T-test is applied for small samples. T-test = (Estimated Mean – Real Mean)/ (square root Estimated variance / n).