Monday, April 30, 2018
Pockets of Predictability
Some months ago I blogged on "Pockets of Predictability," here. The Farmer-Schmidt-Timmermann paper that I mentioned is now available, here.
Monday, April 23, 2018
Ghysels and Marcellino on Time-Series Forecasting
If you're teaching a forecasting course and want a good text, or if you're just looking for an informative and modern treatment, see Applied Economic Forecasting Using Time Series Methods, by Eric Ghysels and Massimilliano Marcellino. It will be published this week by Oxford University Press. It has a very nice modern awareness of Big Data with emphasis on reduced-rank structure, regularization methods -- LASSO appears as early as p. 23! -- , structural change, mixed-frequencies, etc. It's also very tastefully done in terms of what's included and what's excluded, emphasizing what's most important and de-emphasizing the rest. As regards non-linearity, for example, volatility dynamics and regime-switching are in, and most of the rest is out.
Monday, April 16, 2018
The History of Forecasting Competitions
Check out Rob Hyndman's "Brief History of Time Series Forecasting Competitions". I'm not certain whether the title's parallel to Hawking's Brief History of Time is intentional. At any rate, even if Hyndman's focus is rather more narrow than the origin and fate of the universe, his post is still fascinating and informative. Thanks to Ross Askanasi for bring it to my attention.
Monday, April 9, 2018
An Art Market Return Index
Rare and collectible goods, from fine art to fine wine, have many interesting and special aspects. Some are shared and some are idiosyncratic.
From the vantage point of alternative investments (among other things), it would be useful to have high-frequency indices for those asset markets, just as we do for traditional "financial" asset markets like equities.
Along those lines, in "Monthly Art Market Returns" Bocart, Ghysels, and Hafner develop a high-frequency measurement approach, despite the fact that art sales generally occur very infrequently. Effectively they develop a mixed-frequency repeat-sales model, which captures the correlation between art prices and other liquid asset prices that are observed much more frequently. They use the model to extract a monthly art market return index, as well as sub-indices for contemporary art, impressionist art, etc.
Quite fascinating and refreshingly novel.
From the vantage point of alternative investments (among other things), it would be useful to have high-frequency indices for those asset markets, just as we do for traditional "financial" asset markets like equities.
Along those lines, in "Monthly Art Market Returns" Bocart, Ghysels, and Hafner develop a high-frequency measurement approach, despite the fact that art sales generally occur very infrequently. Effectively they develop a mixed-frequency repeat-sales model, which captures the correlation between art prices and other liquid asset prices that are observed much more frequently. They use the model to extract a monthly art market return index, as well as sub-indices for contemporary art, impressionist art, etc.
Quite fascinating and refreshingly novel.
Monday, April 2, 2018
Econometrics, Machine Learning, and Big Data
Here's a useful slide deck by Greg Duncan at Amazon, from a recent seminar at FRB San Francisco (powerpoint, ughhh, sorry...). It's basically a superset of the keynote talk he gave at Penn's summer 2017 conference, Big Data in Predictive Dynamic Econometric Modeling. Greg understands better than most the close connection between "machine learning" and econometrics / statistics, especially between machine learning and the predictive perspective emphasized in time series for a century or so.