# The arboretum procedure

Yüklə 3.07 Mb.

 səhifə 42/148 tarix 30.04.2018 ölçüsü 3.07 Mb.
 : documentationdocumentation -> From cyber-crime to insider trading, digital investigators are increasingly being asked todocumentation -> EnCase Forensic Transform Your Investigationsdocumentation -> File Sharing Documentation Prepared by Alan Halter Created: 1/7/2016 Modified: 1/7/2016documentation -> Gaia Data Release 1 Documentation release 0        Group: ORIGIN*HEAT                        8      0.0092    R2 < MINR2        AOV16: HOMEVAL                           13      0.0091    R2 < MINR2        Class: RACE*NUMCARS                      11      0.0086    R2 < MINR2        Group: RACE*NUMCARS                       5      0.0085    R2 < MINR2        Class: NTITLE*ORIGIN                     23      0.0085    R2 < MINR2        Class: APRTMNT*RACE                       8      0.0084    R2 < MINR2        Group: NTITLE*ORIGIN                      6      0.0084    R2 < MINR2        Additional effects are not listed SS and R2 Portion for Effects Chosen for the Target This section lists the chosen input variables from the forward stepwise regression. The table is divided into the following five columns: Effect lists the sequentially selected effects, which are ranked by the R2 statistic. q    DF shows the degrees of freedom associated with each model effect. q    R2 measures the sequential improvement in the model as input variables are selected. Multiply the R2 statistic by 100 to express it as a percentage. You can interpret the R2 statistic for the LEISURE effect as: "48.27% of the variation in the target AMOUNT is explained by its linear relationship with LEISURE". The R2 statistic for APPAREL indicates that this effect accounts for an additional 13.44% of the target variation. q    SS lists the sums of squares for each model effect. q    EMS lists the Error Mean Square, which measures variation due to either random error or to other inputs that are not in the model. The EMS should get smaller as important inputs are added to the model. Note that although STATECOD has an R2 value greater the STOPR2 cutoff value of 0.005, the error mean square becomes larger when this effect enters the model. q                  SS and R2 portion for Effects chosen for target: AMOUNT       Effect                          DF        R2            SS           EMS     -----------------------------------------------------------------------------   Var:   LEISURE                   1    0.4827     532690709      290726.1      Var:   APPAREL                   1    0.1344     148302146      215325.5      Class: LUXURY                    1    0.0912     100683600      164118.4      Var:   DOMESTIC                  1    0.0489    53918925.2      136706.5      Var:   DPM12                     1    0.0101    11190481.5      131066.8      Class: KITCHEN                   9    0.0086    9486959.66      126808.8      Class: STATECOD                 54    0.0051    5659245.24      127435.3  Note:   Note that the AOV16, GROUP, and two-way class interaction effects are not considered in the forward stepwise regression. Including these effects may produce a better model, but it will also increase the execution time of the DMINE procedure. To learn how to include these effects into the analysis, see Example 2.   The ANOVA table is divided into the following four columns: Effect labels the source of variation as Model, Error, or Total. q    DF lists the degrees of freedom for each source of variation. q    R2 is the model R2, which is the ratio of the model sums of squares (SS) to the total sums of squares. In this q    example, the inputs collectively explain 78.10% of the total variability in the target AMOUNT. SS partitions the total target variation into portions that can be attributed to the model inputs and to error. q                                  DMINE: Continous Target                      The final ANOVA table for target: AMOUNT                   Effect           DF        R2            SS                   -------------------------------------------                   Model            68    0.7810     861932067                   Error          1897               241744735                   Total          1965              1103676802 SS and R2 portion for Effects not chosen for Target The final section lists the sums of squares and the R-square values for the effects that are not chosen in the final model.            SS and R2 portion for Effects not chosen for target: AMOUNT          Effect                             DF        R2            SS          ---------------------------------------------------------------                   Var:   HHAPPAR                      1    0.0022       2405347          Var:   TOWELS                       1    0.0002        213272          Var:   LINENS                       1    0.0000         19937          Var:   HOMEACC                      1    0.0000          8551          Var:   LAMPS                        1    0.0003        351453          Var:   PROMO7                       1    0.0012       1342694          Var:   MENSWARE                     1    0.0027       3016894          Var:   WAPPAR                       1    0.0023       2489091          Var:   BLANKETS                     1    0.0005        517624          Var:   PROMO13                      1    0.0006        641861          Class: DISHES                       9    0.0018       1991598          Var:   COATS                        1    0.0015       1706268 Copyright 2000 by SAS Institute Inc., Cary, NC, USA. All rights reserved. Dostları ilə paylaş:

Verilənlər bazası müəlliflik hüququ ilə müdafiə olunur ©genderi.org 2017
rəhbərliyinə müraciət

Ana səhifə