Probability Flashcards
Probability v. chance
Probability-based on data
Chance-based on whatever’s leftover (errors, unknowns)
40% probability of rain- 40% is based on statistical model, 60% based on unknown variables
What do parametric stats tell us about probability?
In experimental research, we want to know if the IV causes a change in the DV. Our stats tell us what is the probability that it did (and the chance it didn’t)
What is the acceptable probability level in research?
p-value of .05, meaning 95% probability your IV had an effect on DV and 5% chance it did not.
What are we really saying when we say something is statistically significant?
That it’s statistically unlikely we are making a Type I error in inferring an interesting finding. “Statistically noticeable” would be more appropriate. Statistical significance is no guarantee of a big result
Effect size
The strength of the effect (strength of the relationship). This tells us a little more about the significance beyond just the likelihood we aren’t making a Type I error.
