Thursday, December 3, 2009

Boot-Strapped Trends

The use of artificial corrections, the merging of data from different sources, and the curtailing of graphs to hide trends that conflict with your hypothesis, are frowned-upon in High Energy Physics, Engineering, and Neurology, which are my fields, and according to this eloquent comment, they are frowned upon in Medicine as well.

In my experience, these "tricks" (as Phil Jones calls them), allow us to uphold any hypothesis without supporting evidence. In the case of global warming, the tricks went like this. First, we have a trend from global surface stations, which shows a +0.6°C rise in the 20th Century. We claim, but do not prove, that we have accounted for all sources of error. We now receive other observations of temperature. If these new observations agree with our +0.6°C trend, we accept them. The rumor that ice is melting fast and glaciers are retreating is well-received, as are images of polar bears swimming. These new observations, we claim, give us more confidence in our +0.6°C trend. Observations that disagree with our +0.6°C trend we reject. The Briffa tree ring data is curtailed or "smoothed into instrument data" (Gavin Schmidt) in order to "hide the decline" (Phil Jones's). Satellite measurements showed no rise in temperature when they first came out, but this leads us into a flurry of efforts to find sources of error in the analysis that might have hidden the upward trend that we all know must be there from our many supporting temperature observations. Eventually, one or two groups studying satellite data say they see a slight rise. That's good enough. When we combine temperature histories, we give more weighting to those that agree with our hypothesis than those that disagree (see Mann-Made Warming). Our combined trends look great. Now someone comes and challenges our original global surface trend, and we say, "That actual temperatures have been rising is unequivocal and demonstrated by ocean temperatures, retreating glaciers, melting snow, etc. etc. etc." (Gavin Schmidt).

And so our global warming theory pulls itself up by its own bootstraps.

UPDATE: An interview.

1 comment:

  1. Let me explain the basic principle how most Forex systems work. They are tuned up to work in a specific market condition. They often make money in a trending market, but loose money in a choppy market. It is not a problem as long as the market is trending and the system is making more money than it loses. Such a system can be profitable for several months and you would be happy with it. BUT...
    Market change over time. A well designed system starts with trend analysis to stay away from potentially losing trades. There are two problems of how a Forex system recognizes the trend.
    The system responds only to immediate price action. An explosive price movement that is usually the result of news release is tempting people to jump in and make a profit. It looks like a "strong trend", but what usually happens next is a hard fall.
    To avoid falling into this trap, check for the SOLUTION to find a REAL trend:
    Most systems use various indicators to determine the trend. Actually, there is nothing bad about using indicators. One Simply Moving Average can do the job. The problem comes with the question: "Is the market trending NOW?" Whether the market is trending or not trending is not like black and white. The correct question is: "How well the market is trending?"
    And here we have something called TREND RELIABILITY.
    Trends exist and they can be traded up and down for a profit. You have to focus only on the most reliable market trends. "Forex Trendy" is a software solution to find the BEST trending currency pairs, time frames and compute the trend reliability for each Forex chart: