Read simple statistics guides, worked examples, formulas, and explanations designed to help you understand the concepts behind common calculations.
A one-proportion z-test is one of the hypothesis tests used to determine whether a sample proportion is significantly different from a hypothesized population proportion. It is suitable when the outcome…
When performing a hypothesis test for a sample mean where the population standard deviation is known, or when performing one-proportion or two-proportion z-tests, you will often come across the z…
When reading survey results, especially in published work, you might come across a percentage followed by a ± value. For instance, results from a poll may show that 58% ±…
The population mean is the average value of all the observations in the entire group you want to study. It is useful when you have the data for every member,…
The sample mean is the average of observations collected from a subset drawn from a population. Researchers often use it to estimate the population mean, especially when it is not…
Slovin's formula is a statistical formula that is commonly used in research to determine the minimum sample size (n) for a study, when the population size (N) and acceptable margin…
A chi-square table (χ² table), also known as a chi-square critical value table or chi-square distribution table, is a statistical reference table used to determine critical values for chi-square (χ²)…
A 5-number summary is a simple way to describe a dataset using 5-key statistics: the Minimum, First Quartile (Q1), Median (Q2), Third Quartile (Q3), and Maximum. Summarizing your data using…
Descriptive statistics are methods or techniques that are widely used to organize and summarize data in a clear and simple way. In data analysis, descriptive statistics serve as preliminary tests…
The sample mean is the average of a subset of data points collected from a larger population. To calculate the sample mean, you sum all the values in the dataset…