AVS 51st International Symposium
    Applied Surface Science Wednesday Sessions
       Session AS-WeM

Invited Paper AS-WeM5
Chemometric Techniques for Two-way, Three-way and Higher-order Image Data

Wednesday, November 17, 2004, 9:40 am, Room 210A

Session: Chemometric Analysis of Spectral or Image Data; XPS/TOF-SIMS Applications
Presenter: J.M. Shaver, Eigenvector Research, Inc.
Authors: J.M. Shaver, Eigenvector Research, Inc.
B.M. Wise, Eigenvector Research, Inc.
Correspondent: Click to Email
Historically, analytical instrumentation would measure a single response such as intensity or counts as a function of a single parameter such as incident energy (e.g. a spectrum). When this response is measured for a range of samples, one obtains "two-way" data. Each sample gives a single vector of responses. A wide variety of numerical analysis techniques exist for performing quantitative and qualitative analyses of two-way data. However, an increasing number of instruments measure response as a function of multiple parameters such as position on the sample, incident energy, and energy of response. Add to these the measurement of multiple samples and the data can become quite complex with respect to relationships between parameters. One method of analyzing such data is to focus on only one parameter at a time (sample vs. incident intensity) or, alternatively, to ignore the relationship between parameters and string the data into one long series of responses per sample. An more sophisticated approach arranges the data into a multi-way array which can be analyzed for relationships between controlled parameters as a function of sample. This often allows improved accuracy and specificity and, in some cases, is even easier to analyze because of the interrelationships. This paper will discuss the concept of multi-way data and some of the issues associated with its analysis, with particular note to multi-way spectroscopic images.