thyroid-dis

General Description of Thyroid Disease Databases and Related Files This directory contains 6 databases, corresponding test set, and corresponding documentation. They were left at the University of California at Irvine by Ross Quinlan during his visit in 1987 for the 1987 Machine Learning Workshop. The documentation files (with file extension "names") are formatted to be read by Quinlan's C4 decision tree program. Though briefer than the other documentation files found in this database repository, they should suffice to describe the database, specifically: 1. Source 2. Number and names of attributes (including class names) 3. Types of values that each attribute takes In general, these databases are quite similar and can be characterized somewhat as follows: 1. Many attributes (29 or so, mostly the same set over all the databases) 2. mostly numeric or Boolean valued attributes 3. thyroid disease domains (records provided by the Garavan Institute of Sydney, Australia) 4. several missing attribute values (signified by "?") 5. small number of classes (under 10, changes with each database) 7. 2800 instances in each data set 8. 972 instances in each test set (It seems that the test sets' instances are disjoint with respect to the corresponding data sets, but this has not been verified) See the following for a discussion of relevant experiments and related work: Quinlan,J.R., Compton,P.J., Horn,K.A., & Lazurus,L. (1986). Inductive knowledge acquisition: A case study. In Proceedings of the Second Australian Conference on Applications of Expert Systems. Sydney, Australia. Quinlan,J.R. (1986). Induction of decision trees. Machine Learning, 1, 81--106. Note that the instances in these databases are followed by a vertical bar and a number. These appear to be a patient id number. The vertical bar is interpreted by Quinlan's algorithms as "ignore the remainder of this line". ====================================================================== This database now also contains an additional two data files, named hypothyroid.data and sick-euthyroid.data. They have approximately the same data format and set of attributes as the other 6 databases, but their integrity is questionable. Ross Quinlan is concerned that they may have been corrupted since they first arrived at UCI, but we have not yet established the validity of this possibility. These 2 databases differ in terms of their number of instances (3163) and lack of corresponding test files. They each have 2 concepts (negative/hypothyroid and sick-euthyroid/negative respectively). Their source also appears to be the Garavan institute. Each contains several missing values. Another relatively recent file thyroid0387.data has been added that contains the latest version of an archive of thyroid diagnoses obtained from the Garvan Institute, consisting of 9172 records from 1984 to early 1987. A domain theory related to thyroid disease has also been added recently (thyroid.theory). The files new-thyroid.[names,data] were donated by Stefan Aberhard.