In the early 20 th century, Guinness breweries in Dublin had a policy of hiring the best graduates from Oxford and Cambridge to improve their industrial processes. At the time, it was considered a ...

At times we wish to examine statistical evidence, and determine whether it supports or contradicts a claim that has been made (or that we might wish to make) concerning the entire population. This is ...

Adam Hayes, Ph.D., CFA, is a financial writer with 15+ years Wall Street experience as a derivatives trader. Besides his extensive derivative trading expertise, Adam is an expert in economics and ...

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 ...

Investopedia contributors come from a range of backgrounds, and over 25 years there have been thousands of expert writers and editors who have contributed. David Kindness is a Certified Public ...

Editor's Note: This post references research by Diederik Stapel. Many of his studies have since been found to be fradulent. Tomás de Torquemada, "The hammer of heretics," would have loved to hate the ...

What is the Friedman test? The Friedman test, also sometimes referred to as Friedman’s two-way analysis of variance by ranks, is a non-parametric statistical test used to investigate whether groups of ...