# Failing Grade: 89% of Introduction-to-Psychology Textbooks That Define or Explain Statistical Significance Do So Incorrectly

**URL:** <https://onscienceandacademia.org/t/failing-grade-89-of-introduction-to-psychology-textbooks-that-define-or-explain-statistical-significance-do-so-incorrectly/233>\
**Category:** Social sciences\
**Tags:** psychology, p-values, higher\_education\
**Created:** [June 28, 2019, 1:21pm UTC](https://onscienceandacademia.org/t/failing-grade-89-of-introduction-to-psychology-textbooks-that-define-or-explain-statistical-significance-do-so-incorrectly/233 "2019-06-28T13:21:56Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![rebecca](https://sea2.discourse-cdn.com/flex020/user_avatar/onscienceandacademia.org/rebecca/32/520_2.png) [@rebecca](https://onscienceandacademia.org/u/rebecca)\
**Post date:** [June 28, 2019, 1:21pm UTC](https://onscienceandacademia.org/t/failing-grade-89-of-introduction-to-psychology-textbooks-that-define-or-explain-statistical-significance-do-so-incorrectly/233/1 "2019-06-28T13:21:56Z")

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Abstract

Null-hypothesis significance testing (NHST) is commonly used in psychology; however, it is widely acknowledged that NHST is not well understood by either psychology professors or psychology students. In the current study, we investigated whether introduction-to-psychology textbooks accurately define and explain statistical significance. We examined 30 introductory-psychology textbooks, including the best-selling books from the United States and Canada, and found that 89% incorrectly defined or explained statistical significance. Incorrect definitions and explanations were most often consistent with the odds-against-chance fallacy. These results suggest that it is common for introduction-to-psychology students to be taught incorrect interpretations of statistical significance. We hope that our results will create awareness among authors of introductory-psychology books and provide the impetus for corrective action. To help with classroom instruction, we provide slides that correctly describe NHST and may be useful for introductory-psychology instructors.

[https://journals.sagepub.com/doi/abs/10.1177/2515245919858072](https://journals.sagepub.com/doi/abs/10.1177/2515245919858072)