| Converted from Irvine by Ronny Kohavi | *** THIS PROBLEM WAS CHANGED AS FOLLOWS: | 1. The common flares became the only label to predict (the other two | columns were deleted). | 2. The label was changed to binary. Flares or not, i.e., all | numbers > 1 became 1 | 1. TItle: Solar Flare database | | 2. Source Information | -- Donor: Gary Bradshaw | -- Date: 3/89 | | 3. Past Usage: | -- Gary Bradshaw: (Class Attributes were collapsed to 0 and >0) | -- See the past-usage file for a note written by Gary Bradshaw | | 4. Relevant Information: | -- The database contains 3 potential classes, one for the number of times a | certain type of solar flare occured in a 24 hour period. | -- Each instance represents captured features for 1 active region on the | sun. | -- The data are divided into two sections. The second section (flare.data2) | has had much more error correction applied to the it, and has | consequently been treated as more reliable. | | 5. Number of Instances: flare.data1: 323, flare.data2: 1066 | | 6. Number of attributes: 13 (includes 3 class attributes) | | 7. Attribute Information: | 1. Code for class (modified Zurich class) (A,B,C,D,E,F,H) | 2. Code for largest spot size (X,R,S,A,H,K) | 3. Code for spot distribution (X,O,I,C) | 4. Activity (1 = reduced, 2 = unchanged) | 5. Evolution (1 = decay, 2 = no growth, | 3 = growth) | 6. Previous 24 hour flare activity code (1 = nothing as big as an M1, | 2 = one M1, | 3 = more activity than one M1) | 7. Historically-complex (1 = Yes, 2 = No) | 8. Did region become historically complex (1 = yes, 2 = no) | on this pass across the sun's disk | 9. Area (1 = small, 2 = large) | 10. Area of the largest spot (1 = <=5, 2 = >5) | | From all these predictors three classes of flares are predicted, which are | represented in the last three columns. | | 11. C-class flares production by this region Number | in the following 24 hours (common flares) | 12. M-class flares production by this region Number | in the following 24 hours (moderate flares) | 13. X-class flares production by this region Number | in the following 24 hours (severe flares) | | 8. Missing values: None | | 9. Class Distribution: | | flare.data1: | 0 1 2 4 Total | C-class flares 287 29 7 0 323 | M-class flares 291 24 6 2 323 | X-class flares 316 7 0 0 323 | | flare.data2: | | 0 1 2 3 4 5 6 7 8 Total | C-class flares 884 112 33 20 9 4 3 0 1 1066 | M-class flares 1030 29 3 2 1 0 1 0 0 1066 | X-class flares 1061 4 1 0 0 0 0 0 0 1066 0,1 class code : A,B,C,D,E,F,H. largest spot code : X,R,S,A,H,K. spot dist code : X,O,I,C Activity : 1,2. Evolution : continuous. Previous 24 hour code : continuous. Historically-complex :1,2. become complex : 1,2. Area :1,2. Area of the largest spot :1,2.