Joseph Mburu
Joseph is an experienced Statistician and Data Analyst with over six years of hands-on work in applied statistics, data science, and quantitative research. He holds advanced degrees in Applied Statistics and Data Analytics, reflecting strong technical and academic expertise. Joseph is the founder of Stat Study Hub, a platform designed to help students, researchers, and professionals understand statistics through clear explanations, interactive calculators, and practical examples. Known for a friendly, step-by-step teaching approach, he is committed to making statistics simple, accurate, and usable for everyone.
Latest Articles by Joseph Mburu
Z Score: Definition, Formula, Calculation & Interpretation
November 4, 2025
A z score is a statistical measure that shows how many standard deviations a value is from the mean of a dataset. Simply stated, a z score tells you whether a number is above or below the average and by how much. For instance, if you scored 85 on a test where the average was […]
Read MoreHow to Find Probability with Z Score
November 3, 2025
Calculating a z-score is always straightforward. You only need to apply the formula, z =(x−μ)/σ. However, finding probability with a z-score is quite challenging for many students. There are many options for finding probability from a z-score. Some of the ways include an online z-score probability calculator, ti-83/84 z probability calculator, Excel, or z-tables. Z-tables […]
Read MoreFinding Z Score in Excel
October 31, 2025
In statistics, a z-score is a standard score that indicates how many standard deviations a data point is from the mean. For instance, a z value of -2 means that the data point is 2 standard deviations below the mean. To find the z-score value manually, we use the following formula: z=(x−μ)/σ Where Besides applying […]
Read MoreHow to Determine Sample Size: Cochran, Slovin & Yamane
October 11, 2025
When conducting quantitative research and intend to collect primary data using survey questionnaires, you’ll be required to determine the minimum sample size for your study. Sample size determination helps ensure that the results & findings you get are representative of the whole population, without wasting time or resources. While there are many sample size formulas […]
Read MoreFinding Z Critical Value
October 5, 2025
A z-critical value is a cutoff point on a standard normal distribution (z-distribution) used in hypothesis testing to determine whether the results are statistically significant or not. The value is compared with the z-test statistic to determine whether to reject the null hypothesis or not. The decision is to reject the null hypothesis if the […]
Read MoreUnderstanding the Binomial Distribution
September 19, 2025
The binomial distribution is a discrete probability distribution commonly used to model situations where an experiment is repeated a fixed number of times and each trial has only two possible outcomes (success or failure). The outcomes of a binomial experiment are either success or failure, yes or no, or pass or fail. Examples of binomial […]
Read More