A p value less than 0.05 is considered what?

A p value less than 0.05 is considered what?

• A. Statistical significance
• B. Practical significance
• C. Experimental significance
• D. Observational significance

Answer: (A)

The concept being tested is statistical significance. A p value is the probability of obtaining results at least as extreme as what you observed, assuming the null hypothesis is true. When that probability is less than 0.05, we say the result is statistically significant at the 5% level, meaning the observed effect is unlikely to have occurred by chance alone under the null. This tells us about whether to reject the null hypothesis, not about how important or practical the effect is in real-world terms—that’s practical significance. It also isn’t about the study’s design (experimental vs observational) or about a broader notion of significance. The 0.05 threshold is a conventional cutoff, not a universal law.

The concept being tested is statistical significance. A p value is the probability of obtaining results at least as extreme as what you observed, assuming the null hypothesis is true. When that probability is less than 0.05, we say the result is statistically significant at the 5% level, meaning the observed effect is unlikely to have occurred by chance alone under the null. This tells us about whether to reject the null hypothesis, not about how important or practical the effect is in real-world terms—that’s practical significance. It also isn’t about the study’s design (experimental vs observational) or about a broader notion of significance. The 0.05 threshold is a conventional cutoff, not a universal law.