Effect Size Calculation Help for

Dissertation Students & Researchers


What is an Effect Size

     Effect size (ES) is a name given to a family of indices that measure the magnitude of a treatment effect. An effect size is the size of the relationship between two variables and is usually defined as the difference in mean outcomes between the treatment and control group. Effect size is also an indicator of the strength of the difference between two groups. You should specify the effect size you require before collecting or analyzing your data. Several factors influence what effect size one will choose. These factors include theory, standard practice in your particular field, previous or similar research studies, cost, resources and feasibility. There are formulas that can be used to calculate effect size, and some are more complicated than others. Request Effect Size Help Today

Why is Calculating Effect Size Important

     Effect sizes are generally defined as small (d = .2), medium (d = .5), and large (d = .8). In general you need to know the effect size you hope to achieve to calculate statistical power. Knowing the effect size you hope to achieve will save you valuable time and resources.

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Let Us Help You Calculate Your Effect Size

     Given the importance of measuring effect size, it is important that it is conducted properly and explained in simple language. In addition, if you are unsure about how to measure effect size, let us help you calculate your effect size and explain the various components to you. If you are unsure what statistical test might be the most appropriate and powerful for your study, let us review your research question to help you choose the best statistical test for your study. Request Effect Size Help Today