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Re: Back to basics – testing your hypothesis.
Posted by:
Jim Mazerat (IP Logged)
Date: January 22, 2007 02:36PM
I agree there is a difference between science and math and I should have made it clear to the specif area I was addressing. In science, where I believe we are heading in the fire investigation profession, there are three fundamental activities. They are the gathering of data, developing a hypotheses, and test hypotheses, not necessarily in that order. Within these activities, individual may work differently. Data gathering is simply the accumulation of observations — experimental, observational, or mathematical. Hypothesis development requires that it be consistent with all known data, that it fit logically within other accepted hypotheses in science, that it be testable, and that it have predictive power. Hypotheses must be testable within the abilities of science; otherwise they remain simply an idea without use. The hypothesis must also predict that certain phenomena will occur if certain experiments or observations are undertaken. A test must attempt to disprove the hypothesis since proof in science cannot be attained. The more critical tests that a hypothesis passes, the more confidence we can have in it. A single idea, model or hypothesis to explain a set of observations is commonly developed by fire investigators. In the past, a large number of fire investigators stop with the development of an hypothesis that accounts for their observations. However, this method is known to be fraught with many pitfalls. First, a fire investigator with a single hypothesis is like a knight in armor. He is forced to defend his idea because it is the only one that he possesses. Second, data that does not fit the hypothesis are easy to ignore because there is no other place to use it. Thus, the data collected tend to support the hypothesis, yet the best supported hypothesis can still fail on a single critical observation. Third, a fire investigator with a single hypothesis has his or her ego at stake, and thus resists counter hypotheses made by other investigators. Because fire investigators are like other people with regard to their egos, this resistance to alternate hypotheses results in a loss of objectivity, and sometimes bitterness may ensue and controversy abound when others try to disprove the hypothesis.
The method of multiple working hypothesis, is when a fire investigator thinks of all the possible hypotheses that might account for his or her observations, and then goes on to test each one. In this way, his ego is attached not to a single hypothesis, but to the development and testing of all of them. The most efficient known method of advancing science is the "Method of Multiple Working Hypotheses" that entails simultaneous and continuous development and testing of a number of hypotheses. Hypotheses and theories in science are never proven, only disproven. In this sense, a final, a true answer may never be attained, but the supporting evidence, resistance to disproof, and the logical fit with other scientific knowledge provides differing degrees of confidence. By evaluating the degree of confidence, a fire investigator can make valuable decisions about scientific issues and design new technologies even if an answer is not known with certainty.
Based on this is why I developed in our profession of determining the origin and cause of fires we can only disprove our hypothesis.