Paul R. Yarnold Optimal Data Analysis, LLC Growth of classification tree models based upon a secondary a priori performance criterion is demonstrated using a suboptimal classification tree model previously developed using the CHAID algorithm. View journal article

Paul R. Yarnold Optimal Data Analysis, LLC A classification tree pruning methodology that maximizes effect strength for sensitivity is demonstrated for a model which was developed using CART® soft¬ware to predict influenza among primary care patients. View journal article

Paul R. Yarnold Optimal Data Analysis, LLC An optimal model has a specific geometric configuration defined by the number of attributes (“independent variables”—schematically illustrated using circles) and endpoints (defined by response on attribute—indicated by rectangles). Branches direct attributes to endpoints via an if/then/else-based decision rule identified by the (ODA/CTA/novometric) algorithm and operationalized vis-à-vis numerical thresholds … Continue reading The Structure of Perfect Optimal Models with a Two-Category Class Variable and Four or Fewer Endpoints

Paul R. Yarnold Optimal Data Analysis, LLC Two bivariate data sets and four regression models provide the solution. View journal article

Paul R. Yarnold Optimal Data Analysis, LLC Beyond identifying the most accurate classification model which exists for the sample, and estimating cross-generalizability vis-à-vis jackknife, hold-out and/or other validity methods, ODA provides the exact one- or two-tailed P-value, the sensitivity and predictive value for each category of the class variable, and the effect strength corrected for … Continue reading Value-Added by ODA vs. Chi-Square

Paul R. Yarnold Optimal Data Analysis, LLC Research seeking to increase the accuracy of traditional Markov analysis-based models, which assess the outcome (class) variable as a two-category variable, studies the use of over-time weighting schemes. This paper demonstrates how to maximize precision of the class variable by using ODA to weight each individual “observation” (event) … Continue reading Maximum-Precision Markov Transition Table: Successive Daily Change in Closing Price of a Utility Stock