Statistical outliers have been an issue of concern to researchers for over two centuries, and are the focus of this study. Sources of outliers, and various means for dealing with them are discussed. Also presented are general descriptions of univariate outlier tests as well as the two approaches to handling multiple outlier situations, consecutive and block testing. The major problems inherent in these latter methods, masking and swamping, respectively, are recounted. / Specifically, the primary aim of this study is to assess the susceptibility to swamping of four block procedures for multiple outliers in univariate samples. / Pseudo-random samples are generated from a unit normal distribution, and varying numbers of upper outliers are placed in them according to specified criteria. A swamping index is created which reflects the relative vulnerability of each test to declare a block of outliers and the most extreme upper non-outlier discordant, as a unit. / The results of this investigation reveal that the four block tests disagree in their respective susceptibilities to swamping depending upon sample size and the prespecified number of outliers assumed to be present. Rank orderings of these four tests based upon their vulnerability to swamping under varying circumstances are presented. In addition, alternate approaches to calculating the swamping index when four or more outliers exist are described. / Recommendations concerning the appropriate application of the four block procedures under differing situations, and proposals for further research, are advanced. / Source: Dissertation Abstracts International, Volume: 42-01, Section: B, page: 0275. / Thesis (Ph.D.)--The Florida State University, 1981.
Identifer | oai:union.ndltd.org:fsu.edu/oai:fsu.digital.flvc.org:fsu_74401 |
Contributors | WOOLLEY, THOMAS WILLIAM, JR., Florida State University |
Source Sets | Florida State University |
Detected Language | English |
Type | Text |
Format | 141 p. |
Rights | On campus use only. |
Relation | Dissertation Abstracts International |
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