February 8th, 2007, 8:30 pm
QuoteOriginally posted by: bskilton81I would basically say that technical analysis is often an ignorant form of quantitative (or statistical) analysis. I think you'd be hard pressed to find a quant who doesn't believe, for instance, that FX rates display persistent momentum effects (this phenomenon is well documented in academic research). The difference is that if a quant is going to model momentum, he or she does it in a more mathematically rigorous way, doing things like correcting for differences in volatility that would make random noise look like momentum. Usually a technical analyst looks at a charts, makes something up, and then trades on it, without being cognizant of the statistical errors he or she might be making. The best example is the tendency for a chartist to look at equity prices in a graph, while a quant (who probably won't even use a graph), would look at persistence of percentage or log returns (especially if you're looking at a long data set), understanding that this method better captures the statistical dynamics of the market. In fixed income markets, technical analysts may look at bond futures prices, while quants will model yields.Or technical analysts may do a regression on the levels of two equity prices. A quant would be unlikely to do this, because prices are not covariance stationary. Instead, a quant would use log returns. Consequently, a technical analyst is more likely to find a spurious correlation. Edit: I would add that in my limited experience, technical analysts are less cognitive of the covariance matrix of their holdings (they look at a bunch of charts and pick different things based on what they see, and the portfolio tends to be constituted on an ad hoc, spontaneous basis). To a quant making investment decisions, the covariance matrix is the main point of interest, and everything else is just commentary.Nicely put. This pretty much sums up my view on the subject too.Having said that, it is often the case that "ignorant" quant analysis + market intuition > quant analysis + lack of market intuition. Very often, if the idea is sound, a trading strategy will still work even if there implementation is less than perfect. The same cannot be said of the reverse.