1、Chevy versus Ford NASCAR Race Effect Size A Meta-Analysis,Data Description,All 256 NASCAR Races for 1993-2000 Season Race Finishes Among all Ford and Chevy Drivers (Ranks) Ford: 5208 Drivers (20.3 per race) Chevrolet: 3642 Drivers (14.2 per race)For each race, Compute Wilcoxon Rank-Sum Statistic (La
2、rge-sample Normal Approximation)Effect Size = Z/SQRT(NFord + NChevy),Wilcoxon Rank-Sum Test (Large-Sample),Evidence that Chevrolet tends to do better than Ford,Effect Sizes Appear to be approximately Normal,Combining Effect Sizes Across Races,Weighted Average of Race-Specific Effect Sizes Weight Fac
3、tor 1/V(di) = 1/Ni = 1/(NFord,i+NChevy,i),Test for Homogeneity of Effect Sizes,Testing for Year Effects,Testing for Year Effects,Testing for Year and Race/Track Effects,Regression Model Relating Effect Size to: Season (8 Dummy Variables (No Intercept) Track Length Number of Laps Race Length (Track L
4、ength x # of Laps)Weighted Least Squares with weighti = Ni,Regression Coefficients/t-tests,Controlling for all other predictors, none appear significant,C2 Tests for Sub-Models and Overall,Sources,Hedges, L.V. and I. Olkin (1985). Statistical Methods for Meta-Analysis, Academic Press, Orlando, FL. Winner, L. (2006). “NASCAR Winston Cup Race Results for 1975-2003,” Journal of Statistical Education, Volume 14, #3 www.amstat.org/publications/jse/v14n3/datasets.winner.html,
