POLS 625

Exam 2 Review Sheet

Last Updated: Nov 21, 2014


This review is intended to give you a general idea of what may appear on the exam. The exam will cover material from the assigned readings and material that was presented in the lecture.


I. Determining What to Avoid

Indeterminate research designs

††††††††††††††††††††††† More inferences than observations

††††††††††† Multicollinearity

Selection bias

Intentional selection of observations

††††††††††† Measurement error

††††††††††††††††††††††† Systematic measurement error and nonsystematic measurement error

††††††††††† Excluding relevant variables: Bias

††††††††††† Including irrelevant variables: Inefficiency


II. Types of Data

††††††††††† Cross-sectional, time series, panel (cross-sectional time-series)††††

III. Test of Significance

††††††††††† One sample case- z (computation)

††††††††††† One sample case- t (computation, SPSS)

†††† †††††† Chi square test (computation, SPSS)

††††††††††† t-test for Pearsonís correlation (computation)

III. Measures of Association

A. Nominal and ordinal variables


††††††††††† Know how to produce a cross-tabulation manually

††††††††††† Know how to read a cross-tabulation (both bivariate and multivariate)††

††††††††††† Know how to control for a third variable (Nominal and ordinal variables only)

††††† Tests of statistical significance and measures of association (SPSS)

††††††††††† Know how to write a hypothesis

††††††††††† Know how to test a hypothesis

††††††††††††††††††††††† Statistical significance

††††††††††††††††††††††† Strength of association

††††††††††††††††††††††††††††††††††† Know how to calculate Lambda manually

††††††††††††††††††††††† Direction of association

††††††††††††††††††††††† Substantive interpretation

††††† Bivariate association

††††††††††††††††††††††† Lambda, Cramerís V, Somerís d (SPSS, interpretation)

††††† Controlling for a third variable (where the third variable is a nominal or ordinal variable)

††††††††††††††††††††††† Lambda, Cramerís V, Somerís d (SPSS, interpretation)

B. I/R variables

†††† Pearsonís r (Computation including testing a hypothesis, Excel, SPSS, interpretation)†††††††

†† Bivariate regression (Manually computing intercept and slope, Excel, SPSS, interpretation)

†† Multiple regression (SPSS, interpretation)

IV. Five Phases of Research Paper


The following formulae and tables will be provided.

I. Formulae






Chi square:






Pearson's r





Regression (Bonus points for manual calculation)




II. The z, t, and chi square tables and the summary table below


Levels of Measurement

Measures of Association

Two nominal variables

Lambda/Cramerís V

Two ordinal variables

Somerís d

I/R variables

Pearsonís correlation


III. Bonus points (2 points): Weighted average.