Cause and Effect _ Statistical Significance

Front

A football coach tests if yoga improves player flexibility and reduces injuries by dividing his team into two groups: one does yoga, the other standard stretching. Can results be generalized?

Back

No, since the coach only used players on his team.

Front

A football coach tests if yoga improves player flexibility and reduces injuries by dividing them into two groups: one with yoga and one with standard stretching. Can we claim cause and effect?

Back

Yes, since the coach has divided the players into two treatment groups randomly.

Front

Does lack of sleep affect academic performance? A student asks his statistics class for test scores and sleep hours. Can results be generalized?

Back

No, since he only used his statistics class.

Front

Lack of sleep's effect on academic performance: observational study findings.

Back

No, since this was an observational study.

Front

A marketing executive tests a new cookie package in 45 randomly-selected grocery stores. Can results be generalized?

Back

Yes, we can generalize to all the grocery stores in the city since they were randomly selected.

Front

Marketing exec tests new cookie packaging in 45 stores, comparing sales to last month. Can we claim cause and effect?

Back

No, comparing the sales is not an experiment.

Front

Simulation showed 0% chance of guessing 11/12 correct for Alzheimer's. Statistically significant?

Back

Yes, 0% < 5%

Front

Statistical significance indicates a probability of...

Back

Less than .05