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Title: AUTOMATED RESOLUTION OF MULTI-EXPONENTIAL DECAY DATA - CHAPTER 14

Author
item RUSLING, JAMES - UNIV OF CONNECTICUT
item Kumosinski, Thomas

Submitted to: Nonlinear Computer Modeling of Chemical and Biochemical Data
Publication Type: Book / Chapter
Publication Acceptance Date: 5/4/1995
Publication Date: N/A
Citation: N/A

Interpretive Summary: Book chapter - interpretive summary is not required.

Technical Abstract: It has been previously shown that exponential decay of a signal can be used to extensively illustrate various aspects of nonlinear regression analysis. Analysis of this type of data is quite important for processes such as luminescence decay, radioactive decay, and irreversible first-order chemical reactions. Often, data containing two or more time constants are encountered. For example, mixtures of species which are all undergoing first-order decay with differing lifetimes where the appropriate model is comprised of sums of exponentials. This model requires a judgment concerning the correct number of exponentials which best fits the data. The problem is complicated by the fact that each successive higher order model contains two more parameters than its predecessor. Thus, in this chapter it is shown that the best model can be chosen relying on comparisons of deviation plots, and the extra sum of squares F- test. The extra sum of squares F-test provides a statistical probability of best fit which corrects for the different number of parameters in two model analyses. Resolution of multiple exponentials becomes difficult when three or more exponentials overlap, this problem is discussed in detail in this chapter.