'How large a sample do I need?' is one of the most commonly asked questions of a statistician. It is also one of the hardest questions to answer. The researcher posing the query usually believes, ...

There are a large number of different definitions used for sample quantiles in statistical computer packages. Often within the same package one definition will be used to compute a quantile explicitly ...

What is a one sample t test? The t test is a commonly used hypothesis test in statistics that allows us to compare the mean value of a group of sampled data with some hypothesized value, usually a ...

High-dimensional categorical data models, often with inadequately large sample sizes, crop up in many fields of application. The SARS epidemic, originating in southern China in 2002, had an identified ...

Investopedia contributors come from a range of backgrounds, and over 25 years there have been thousands of expert writers and editors who have contributed. Dr. JeFreda R. Brown is a financial ...