Data: Quantitative (Histogram, Stem & Leaf, Boxplots) versus Categorical (Bar or Pie Chart)...

• Data: Quantitative (Histogram, Stem & Leaf, Boxplots) versus Categorical (Bar or Pie Chart)

• Boxplots: 5 Number Summary, IQR, Outliers???, Comparisons

• Center, Shape & Spread!• For Skewed Data use…median & IQR• For Symmetric data use…mean & SD

• Normal Model (68 - 95 - 99.7), SD & z-scores

• Linear Regression: Explanatory and response variables.

• Association versus Correlation• Correlation Coefficient - strength and

direction• Residuals• R-squared• Influential Points (leverage) & outliers• Extrapolation• Ladder of Powers

• Random Digits & Simulations– Identify component– Explain how model outcome– Explain how simulate trial– State response variable– Run trials– Analyze response variable– State conclusion in context

• Surveys– Population versus sample– SRS– Randomizing & representative– Sampling Variability– Design:

• Stratified• Cluster• Systematic

• Watch out for bias!!!– Voluntary– Convenience– Under-coverage– Non-response– Response

• Observational Studies– Retrospective versus prospective

• Experiments– Random assignment of subjects– Level, factor & treatments– 4 principles of experimental design

• Control extraneous variation• Randomize subjects• Replicate• Block & blind

– Statistically significant???– Control versus placebo– Best experiments are randomized, comparative (control),

double-blind & placebo-controlled!!!

– Matched Pairs• Match subjects that are similar in ways not under

study (ex: right & left feet)

– Randomized Block Design– Causation?

• If only possible explanation for the difference is…

– Lurking versus confounding variables

• Probability Rules– Complement– Addition Rule (Disjoint)– General Addition Rule– Multiplication Rule (Independent)– Conditional Probabilities & Independence– Tree Diagrams

• Random Variables– Expected Value– Standard Deviation– Means & Variances

• Factors– Change mean & variance

• Addends– Change mean but not variance

• Combining Random Variables– Means Add or Subtract– Always add variances

• Probability Models– Geometric

• When do we see the first success???• Conditions• Expected Value & SD

– Binomial• k successes in n trials• Conditions• Expected Value & Standard Deviation

• Write the hypothesis & conditions for the following…– 1 Proportion z-test– 2 Proportion z-Test– 1 Sample t-test– 2 Sample t-test– Paired Data– Chi-Squared Family of Tests– Slope of regression line

M.C. Tips

• Underline key words

• Write out your procedure

• Don’t Rush

• Balance your time (2-3 min per ???)

F.R. Tips

• Do easier ???’s first

• Answer the ??? Asked (underline)

• If miss 1 part, answer a part you know

• Inference: Conditions/Mechanics/Conclusion

• Be concise

• Verify conditions (not just a checklist)

• 2 decimal places for z-scores, 4 for p-values

• Context is King!!!

Multiple Choice Answers