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• 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