How do you know which ones are the good ones, Steven? It seems like a situation similar to the evaluation of mutual fund managers:
http://www.ifa.com/12steps/step5/step5page2.asp
“Unlike the 20-year characteristic of an index, the past performance of money managers has no bearing on their future performance. Every reputable study of mutual fund performance over the past 30 years has found there is no reliable way to know if past superior managers will win again in the future. This is why some variation of the disclaimer “past performance is no guarantee of future results” must appear in all mutual fund advertisements and prospectuses, even though the SEC allows it to be written in very small print.
Studies show that those who have outperformed some past benchmark are more likely to underperform it in the future. Burton Malkiel, author of the long-time investment best seller, A Random Walk Down Wall Street, conducted a study in 1995. In the study’s conclusion, he states, “It does not appear that one can fashion a dependable strategy of generating excess returns based on a belief that long-run mutual fund returns are persistent.””
Maybe the models that most closely match recent climate data just got lucky. Maybe we are looking at what is essentially a Random Walk Down Climate Street. What say you, Mr. Mosher?
