Understanding Statistical Significance Using t-Tests
What is Statistical Significance?
In sports science research, we often need to determine if the differences we observe between two groups are meaningful or just due to chance. This is where statistical significance comes in, and the t-test is our go-to tool for this purpose.
NoteStatistical significance tells us how confident we can be that our results represent a real difference rather than random variation.
The t-Test Process
- Calculate the t-value using your data
- Find the degrees of freedom (df)
- Look up the critical t-value in a t-table
- Compare your calculated t-value with the critical value
Understanding Critical Values
The critical value represents our threshold for significance. We typically use:
- p = 0.05 (95% confidence level)
- p = 0.01 (99% confidence level)
The larger your calculated t-value compared to the critical value, the more confident you can be that there's a real difference between your groups.
Making the Decision
Rules for Interpretation:
- If calculated t > critical t: Significant difference exists
- If calculated t ≤ critical t: No significant difference
