Tarmo: Thanks for your thoughtful response to my facetious post.
Best wishes, John Tarmo Veskioja wrote: > > > John Randall wrote: > >>Tarmo: >> >>Thanks for the explanation. I guess I still do not get the reliance >> today >>on a rule of thumb method to approximate eigenvalues when there has been >>technology to do it accurately for many years. >> >>- The power method and similar iterative methods are easy to program. >> >>- Engineers have calculated eigenvalues on computers since the 1950s. >> >>- The routines that later were incorporated into EISPACK (and then >> LAPACK) >>were originally written in ALGOL in 1971. >> >>- IMSL and NAG have been going since the early 1970s. >> >>- Maple started in 1980. >> >>- MATLAB and Mathematica started in 1985. >> >>Where have you guys been? >> >> > I'm afraid I wasn't even born yet when Saaty first postulated his AHP > principles (around 1973). > > The power method is known in the AHP circles for a long time, but the > use of simple first iteration has persisted, especially as a teaching > example. AHP has mostly been marketed in social sciences and towards > management. I think that is the reason why the teaching material has > been kept as simple as possible. And as I said before, if the pairwise > comparisons have been made by people, then the differences (exact / > inexact, left/right) are usually perceived to be so small that the > results are more sensitive to subjective judgements (or missing > criteria) than to choosing the right eigenvector method. With subjective > judgements AHP is not an exact science. If the pairwise comparisons are > based on objective data that has been transformed to the relative scale, > then the precision is more important. > Compared to BOGSAT decision process (bunch of old guys/gals sitting > around the table - kind of like king Arthur's roundtable or the > veetshe/senate of Novgorod), AHP or any multicriteria decision making > process is a success. > > There are 5 sources of information that I would recommend: > www.expertchoice.com > www.superdecisions.com > http://www.creativedecisions.net/ > http://mdm.gwu.edu/Forman/ > Web-HIPRE: > http://www.hipre.hut.fi/ > > With best wishes, > Tarmo > > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm > ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
