Date of Graduation
8-2018
Document Type
Dissertation
Degree Name
Doctor of Philosophy in Business Administration (PhD)
Degree Level
Graduate
Department
Accounting
Advisor/Mentor
Vern Richardson
Committee Member
James Myers
Second Committee Member
David Douglass
Third Committee Member
Cory Cassell
Keywords
Changes In Earnings, Data Analytics, Machine Learning
Abstract
This paper investigates whether the accuracy of models used in accounting research to predict categorical dependent variables (classification) can be improved by using a data analytics approach. This topic is important because accounting research makes extensive use of classification in many different research streams that are likely to benefit from improved accuracy. Specifically, this paper investigates whether the out-of-sample accuracy of models used to predict future changes in earnings can be improved by considering whether the assumptions of the models are likely to be violated and whether alternative techniques have strengths that are likely to make them a better choice for the classification task. I begin my investigation using logistic regression to predict positive changes in earnings using a large set of independent variables. Next, I implement two separate modifications to the standard logistic regression model, stepwise logistic regression and elastic net, and examine whether these modifications improve the accuracy of the classification task. Lastly, I relax the logistic regression parametric assumption and examine whether random forest, a nonparametric machine learning technique, improves the accuracy of the classification task. I find little difference in the accuracy of the logistic regression-based models; however, I find that random forest has consistently higher out-of-sample accuracy than the other models. I also find that a hedge portfolio formed on predicted probabilities using random forest earns larger abnormal returns than hedge portfolios formed using the logistic regression-based models. In subsequent analysis, I consider whether the documented improvements exist in an alternative classification setting: financial misstatements. I find that random forest’s out-of-sample area under the receiver operating characteristic (AUC) is significantly higher than the logistic-based models. Taken together, my findings suggest that the accuracy of classification models used in accounting research can be improved by considering the strengths and weaknesses of different classification models and considering whether machine learning models are appropriate.
Citation
Hunt, J. (2018). Predicting Changes in Earnings: A Walk Through a Random Forest. Graduate Theses and Dissertations Retrieved from https://scholarworks.uark.edu/etd/2856