What does effect size mean?

Definitions for effect size

Here are all the possible meanings and translations of the word effect size.


  1. effect size(Noun)

    A measure of the strength or magnitude of the effect of an independent variable on a dependent variable in an experiment or a quasi-experiment.


  1. Effect size

    In statistics, an effect size is a measure of the strength of a phenomenon or a sample-based estimate of that quantity. An effect size calculated from data is a descriptive statistic that conveys the estimated magnitude of a relationship without making any statement about whether the apparent relationship in the data reflects a true relationship in the population. In that way, effect sizes complement inferential statistics such as p-values. Among other uses, effect size measures play an important role in meta-analysis studies that summarize findings from a specific area of research, and in statistical power analyses. The concept of effect size already appears in everyday language. For example, a weight loss program may boast that it leads to an average weight loss of 30 pounds. In this case, 30 pounds is an indicator of the claimed effect size. Another example is that a tutoring program may claim that it raises school performance by one letter grade. This grade increase is the claimed effect size of the program. These are both examples of "absolute effect sizes", meaning that they convey the average difference between two groups without any discussion of the variability within the groups. For example, if the weight loss program results in an average loss of 30 pounds, it is possible that every participant loses exactly 30 pounds, or half the participants lose 60 pounds and half lose no weight at all.


  1. Chaldean Numerology

    The numerical value of effect size in Chaldean Numerology is: 4

  2. Pythagorean Numerology

    The numerical value of effect size in Pythagorean Numerology is: 5

Sample Sentences & Example Usage

  1. Lisanne Blauw:

    We were surprised though by the magnitude of the effect size, we calculated that a 1-degree Celsius rise in environmental temperature could account for more than 100,000 new diabetes cases per year in the USA alone.

Images & Illustrations of effect size

  1. effect sizeeffect sizeeffect size

Translations for effect size

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"effect size." Definitions.net. STANDS4 LLC, 2018. Web. 23 Mar. 2018. <https://www.definitions.net/definition/effect size>.

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