Z Score Calculator Z Score to Percentile Calculator Left Tailed Test. H 1: parameter < value. Notice the inequality points to the left. Decision Rule: Reject H 0 if t.s. < c.v.. Right Tailed Test. H 1: parameter > value. Notice the inequality points to the rightUsing the calculator above, you find that a difference in sample proportions of 3% [3% = 20% - 17%] would results in a z-score of 2.73 under the null distribution, which translates to a p-value of 0.63%.

Z Score Calculator to compare the relative standings of items. All the items from distributions with different means and/or different standard deviations. Z Score Formula. where. σ is the standard deviation of the population. μ is the mean of the population. x is a raw score to be standardized Jan 07, 2018 · Here we consider the z score value to be of negative i.e. -2.00 to find the data to the right of the z score if plotted on a standard normal distribution, and when we look at the Table of Standard Normal Probabilities for Negative Z-scores to find the percentage of students who scored more than 130, it comes out to be 2.28%.