Understanding Significance and Inferential Statistics

What is the concept of significance?

• Any difference between groups that is due to chance

• Any difference between groups that is due to a systematic influence

• The degree of risk you are willing to take that you will reject a null hypothesis when it is actually true

• The risk associated with not being 100% positive that what occurred in the experiment is a result of what is being tested

What is a Type I error?

• Failing to reject a null hypothesis when it is true

• Rejecting a null hypothesis when it is true

• Failing to reject a false null hypothesis

• Rejecting a null hypothesis when there are differences between the two groups

What is a Type II error?

• Failing to reject a null hypothesis when it is true

• Rejecting a null hypothesis when it is true

• Failing to reject a false null hypothesis

• Rejecting a null hypothesis when there are differences between the two groups

What does statistical significance represent?

• The probability of observing an outcome less than 0.05

• The probability of observing an outcome greater than 0.05

• The probability of observing an outcome equal to 0.05

• The probability of observing an outcome greater than or equal to 0.05

What is the goal of scientific research?

• To achieve statistical significance

• To achieve meaningful results

• To minimize Type I errors

• To minimize Type II errors

What are the steps involved in inferential statistics?

• Select representative samples, collect relevant data, reach a conclusion based on chance, apply the conclusion to the whole population

• Select representative samples, collect relevant data, reach a conclusion based on systematic influence, apply the conclusion to the whole population

• Select random samples, collect irrelevant data, reach a conclusion based on chance, apply the conclusion to the whole population

• Select random samples, collect relevant data, reach a conclusion based on systematic influence, apply the conclusion to the whole population

How do you select the appropriate statistical test?

• Answer the questions in Figure 11.1

• Answer the questions in Table 11.1

• Answer the questions in Appendix B

• Answer the questions in Table B.1

What is a confidence interval?

• The range of a population value given the sample value

• The range of a sample value given the population value

• The range of a population value given the population value

• The range of a sample value given the sample value

Tags

NGSS.HS-LS3-3

What does a 95% confidence interval mean?

• The sample value is within 1.96 standard deviations of the population value

• The sample value is within 2.56 standard deviations of the population value

• The population value is within 1.96 standard deviations of the sample value

• The population value is within 2.56 standard deviations of the sample value

What can be learned from the discussion of statistical versus clinical significance?

• Statistical significance is always more important than clinical significance

• Clinical significance is always more important than statistical significance

• Large clinical trials often have statistically significant results with clinically irrelevant differences

• Large clinical trials often have statistically insignificant results with clinically relevant differences