

Statistical Significance Versus Practical Significance


Statistical significance is essentially scientific credibility. In many
academic
disciplines, research is considered statistically significant
only if the
results of the study would occur by mere chance less than five times out
of 100 (21). For many, this number has
become a kind of
gold standard, often determining which papers are published,
where researchers find work, etc.
As a consumer of numbers, this is important to you for two reasons.
1. Do not trust studies with extremely low statistical significance. 2. Remember that 5 out of 100 is an arbitrary cutoff which establishes statistical significance. What it doesn't determine is practical significance. Loads of weight is given to this number, when practically, it may not prove all that meaningful. For example, consider the difference between something occurring by chance four times out of 100 instead of six times out of 100. Depending on the situation, this difference could prove either ridiculous or crucial. Next :Do Churches Cause Crime? Previous: Statistics Home 
