Udacity Stat 95 Exam 1 Study Guide

For the exam, you should be familiar with the following concepts. Please note that due to time constraints not all concepts will appear on the exam.

1. Constructs: defined, be able to recognize examples
2. Operational definitions: defined, be able to recognize examples
3. Variables: defined
4. Lurking or extraneous variables: defined, be able to recognize examples
5. Hypotheses: defined
6. Sampling error: defined
7. Populations vs. Samples: know the difference between them; be able to recognize examples
8. Parameter vs. Statistic: know the difference between them; be able to recognize examples
9. Random sampling (selection) vs. random assignment: know the difference between them and the purposes of each
10. Experimental studies: characteristics, variables involved (independent, dependent, controlled, lurking); causal inference; placebo control; control (comparison) groups; blinding, double-blind procedures
11. Observational studies: characteristics, variables involved (predictor, outcome, lurking); no causal inference
12. Survey studies: characteristics, strengths (e.g., easy to conduct), limitations (e.g., non- response bias)
13. Frequency distributions: symmetrical, skewed; be able to read and create tables and graphs (determine frequencies, proportions, percentages, mode, and N).
14. Bar graphs vs. histograms; know when to use each
15. Summation notation: know how to use it to get the mean, sum of squares (SS), variance, and standard deviation (SD)
16. Measures of central tendency: Mean, median, mode (know how to compute each and when each is appropriate); know the properties of the mean; know the locations of the three measures in skewed and normal distributions
17. Outliers: definition; effects on the mean, SD
18. Measures of variability: range, IQR, SS, variance, SD; know how to compute the SS, variance and SD (for both populations and samples); know how to interpret the SD and variance in conjunction with the mean