On desensitizing data from interval to nominal measurement with minimum information loss.
Published: 2004
Language: eng
Number of pages: 107
Subjects: Multidimensional scaling.; Scaling (Social sciences).
Description: Given a dataset of continuous variables full of nonlinear relationships, dual scaling analysis of the discretized data will make it possible to capture both linear and nonlinear relations, which principal component analysis (PCA) of original continuous data would fail to accomplish. Dual scaling (DS) is known as principal component analysis of categorical data (PCAC), a comprehensive framework of multidimensional analysis of categorical data that covers both incidence data and dominance data.When continuous data are treated as nominal data, the number of options may be quite large, leading to a large number of solutions, which may not even be interpretable. Therefore, it is legitimate to wonder (1) how many intervals would be optimal? (2) How should one categorize continuous variable so as to capture most of the information in the data?In this thesis, a search method called the maximum exhaustiveness coefficient algorithm (MECA) is proposed as an efficient way to discretize continuous data for dual scaling analysis of continuous data. MECA minimizes the discriminative information loss inherent in the discretization process while maximizing the exhaustiveness coefficient of the cross-classification. A condition typically deemed desirable from a dual scaling of multiple-choice data is imposed, namely that the optimal number of categories for a variable be between 3 and 6. MECA provides sets of thresholds determining both the number of intervals and their respective width for each variable.
Notes: Adviser: Shizuhiko Nishisato.

Thesis (Ph.D.)--University of Toronto, 2004.

Electronic version licensed for access by U. of T. users.

Source: Dissertation Abstracts International, Volume: 65-10, Section: B, page: 5218.