Monthly Archives: June 2014

Data snooping in a nutshell

Data snooping is pervasive in financial research, both in academia and in industry. In my experience, the level of awareness about data snooping varies widely among practitioners. All too often, however, huge amounts of time and effort are wasted by following a … Continue reading

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Noise in asset returns

One of the goals of this blog is to discuss various approaches to forecasting asset returns taken from both the economics and machine learning fields. Before diving into specific models and techniques, however, I begin by discussing the issue of noise in … Continue reading

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The Hedgehog and the Fox Redux

Many fund managers will be aware of Philip Tetlock’s book “Expert Political Judgment” published in 2005. In the book, Tetlock analyzes forecasts collected from 284 experts over twenty years. While he focuses primarily on the ability of political experts to … Continue reading

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Is out-of-sample testing of forecasting models a myth?

When working with forecasting models, a well-known observation is that in-sample performance is usually better, often much better, than out-of-sample performance. That is, a model generally produces better forecasts over the data that it was constructed on than over new data. … Continue reading

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