6.3 Prediction Details

Prediction details are XML strings that provide information about the score. Details are available for all types of scoring: clustering, feature extraction, classification, regression, and anomaly detection. Details are available whether scoring is dynamic or the result of model apply.

The details functions, CLUSTER_DETAILS, FEATURE_DETAILS, and PREDICTION_DETAILS return the actual value of attributes used for scoring and the relative importance of the attributes in determining the score. By default, the functions return the five most important attributes in descending order of importance.

6.3.1 Cluster Details

For the most likely cluster assignments of customer 100955 (probability of assignment > 20%), the query in the following example produces the five attributes that have the most impact for each of the likely clusters. The clustering functions apply an Expectation Maximization model named em_sh_clus_sample to the data selected from mining_data_apply_v. The "5" specified in CLUSTER_DETAILS is not required, because five attributes are returned by default.

Example 6-6 Cluster Details

SELECT S.cluster_id, probability prob,
           CLUSTER_DETAILS(em_sh_clus_sample, S.cluster_id, 5 USING T.*) det
      (SELECT v.*, CLUSTER_SET(em_sh_clus_sample, NULL, 0.2 USING *) pset
        FROM mining_data_apply_v v
       WHERE cust_id = 100955) T,
      TABLE(T.pset) S
---------- ----- ----------------------------------------------------------------------------
        14 .6761 <Details algorithm="Expectation Maximization" cluster="14">  
                 <Attribute name="AGE" actualValue="51" weight=".676" rank="1"/>
                 <Attribute name="HOME_THEATER_PACKAGE" actualValue="1" weight=".557" rank="2"/>
                 <Attribute name="FLAT_PANEL_MONITOR" actualValue="0" weight=".412" rank="3"/>
                 <Attribute name="Y_BOX_GAMES" actualValue="0" weight=".171" rank="4"/>
                 <Attribute name="BOOKKEEPING_APPLICATION"actualValue="1" weight="-.003"
         3 .3227 <Details algorithm="Expectation Maximization" cluster="3">
                 <Attribute name="YRS_RESIDENCE" actualValue="3" weight=".323" rank="1"/>
                 <Attribute name="BULK_PACK_DISKETTES" actualValue="1" weight=".265" rank="2"/>
                 <Attribute name="EDUCATION" actualValue="HS-grad" weight=".172" rank="3"/>
                 <Attribute name="AFFINITY_CARD" actualValue="0" weight=".125" rank="4"/>
                 <Attribute name="OCCUPATION" actualValue="Crafts" weight=".055" rank="5"/>

6.3.2 Feature Details

The query in the following example returns the three attributes that have the greatest impact on the top Principal Components Analysis (PCA) projection for customer 101501. The FEATURE_DETAILS function applies a Singular Value Decomposition model named svd_sh_sample to the data selected from svd_sh_sample_build_num.

Example 6-7 Feature Details

SELECT FEATURE_DETAILS(svd_sh_sample, 1, 3 USING *) proj1det
  FROM svd_sh_sample_build_num
  WHERE CUST_ID = 101501;
<Details algorithm="Singular Value Decomposition" feature="1">
<Attribute name="HOME_THEATER_PACKAGE" actualValue="1" weight=".352" rank="1"/>
<Attribute name="Y_BOX_GAMES" actualValue="0" weight=".249" rank="2"/>
<Attribute name="AGE" actualValue="41" weight=".063" rank="3"/>

6.3.3 Prediction Details

The query in the following example returns the attributes that are most important in predicting the age of customer 100010. The prediction functions apply a Generalized Linear Model Regression model named GLMR_SH_Regr_sample to the data selected from mining_data_apply_v.

Example 6-8 Prediction Details for Regression

SELECT cust_id,
      PREDICTION(GLMR_SH_Regr_sample USING *) pr,
  FROM mining_data_apply_v
  WHERE CUST_ID = 100010;
------- ----- -----------
 100010 25.45 <Details algorithm="Generalized Linear Model">
              <Attribute name="FLAT_PANEL_MONITOR" actualValue="1" weight=".025" rank="1"/>
              <Attribute name="OCCUPATION" actualValue="Crafts" weight=".019" rank="2"/>
              <Attribute name="AFFINITY_CARD" actualValue="0" weight=".01" rank="3"/>
              <Attribute name="OS_DOC_SET_KANJI" actualValue="0" weight="0" rank="4"/>
              <Attribute name="BOOKKEEPING_APPLICATION" actualValue="1" weight="-.004" rank="5"/>

The query in the following example returns the customers who work in Tech Support and are likely to use an affinity card (with more than 85% probability). The prediction functions apply an Support Vector Machine (SVM) Classification model named svmc_sh_clas_sample. to the data selected from mining_data_apply_v. The query includes the prediction details, which show that education is the most important predictor.

Example 6-9 Prediction Details for Classification

SELECT cust_id, PREDICTION_DETAILS(svmc_sh_clas_sample, 1 USING *) PD
      FROM mining_data_apply_v
  WHERE PREDICTION_PROBABILITY(svmc_sh_clas_sample, 1 USING *) > 0.85
  AND occupation = 'TechSup'
  ORDER BY cust_id;
------- ---------------------------------------------------------------------------------------
 100029 <Details algorithm="Support Vector Machines" class="1">
        <Attribute name="EDUCATION" actualValue="Assoc-A" weight=".199" rank="1"/>
        <Attribute name="CUST_INCOME_LEVEL" actualValue="I: 170\,000 - 189\,999" weight=".044"
        <Attribute name="HOME_THEATER_PACKAGE" actualValue="1" weight=".028" rank="3"/>
        <Attribute name="BULK_PACK_DISKETTES" actualValue="1" weight=".024" rank="4"/>
        <Attribute name="BOOKKEEPING_APPLICATION" actualValue="1" weight=".022" rank="5"/>
 100378 <Details algorithm="Support Vector Machines" class="1">
        <Attribute name="EDUCATION" actualValue="Assoc-A" weight=".21" rank="1"/>
        <Attribute name="CUST_INCOME_LEVEL" actualValue="B: 30\,000 - 49\,999" weight=".047"
        <Attribute name="FLAT_PANEL_MONITOR" actualValue="0" weight=".043" rank="3"/>
        <Attribute name="HOME_THEATER_PACKAGE" actualValue="1" weight=".03" rank="4"/>
        <Attribute name="BOOKKEEPING_APPLICATION" actualValue="1" weight=".023" rank="5"/>
 100508 <Details algorithm="Support Vector Machines" class="1">
        <Attribute name="EDUCATION" actualValue="Bach." weight=".19" rank="1"/>
        <Attribute name="CUST_INCOME_LEVEL" actualValue="L: 300\,000 and above" weight=".046"
        <Attribute name="HOME_THEATER_PACKAGE" actualValue="1" weight=".031" rank="3"/>
        <Attribute name="BULK_PACK_DISKETTES" actualValue="1" weight=".026" rank="4"/>
        <Attribute name="BOOKKEEPING_APPLICATION" actualValue="1" weight=".024" rank="5"/>
 100980 <Details algorithm="Support Vector Machines" class="1">
        <Attribute name="EDUCATION" actualValue="Assoc-A" weight=".19" rank="1"/>
        <Attribute name="FLAT_PANEL_MONITOR" actualValue="0" weight=".038" rank="2"/>
        <Attribute name="HOME_THEATER_PACKAGE" actualValue="1" weight=".026" rank="3"/>
        <Attribute name="BULK_PACK_DISKETTES" actualValue="1" weight=".022" rank="4"/>
        <Attribute name="BOOKKEEPING_APPLICATION" actualValue="1" weight=".02" rank="5"/>

The query in the following example returns the two customers that differ the most from the rest of the customers. The prediction functions apply an anomaly detection model named SVMO_SH_Clas_sample to the data selected from mining_data_apply_v. Anomaly Detection uses a one-class SVM classifier.

Example 6-10 Prediction Details for Anomaly Detection

SELECT cust_id, pd FROM
  (SELECT cust_id,        
         PREDICTION_DETAILS(SVMO_SH_Clas_sample, 0 USING *) pd,
         RANK() OVER (ORDER BY prediction_probability(
               SVMO_SH_Clas_sample, 0 USING *) DESC, cust_id) rnk
  FROM mining_data_one_class_v)
  WHERE rnk <= 2
  ORDER BY rnk;

---------- -----------------------------------------------------------------------------------
    102366 <Details algorithm="Support Vector Machines" class="0">
           <Attribute name="COUNTRY_NAME" actualValue="United Kingdom" weight=".078" rank="1"/>
           <Attribute name="CUST_MARITAL_STATUS" actualValue="Divorc." weight=".027" rank="2"/>
           <Attribute name="CUST_GENDER" actualValue="F" weight=".01" rank="3"/>
           <Attribute name="HOUSEHOLD_SIZE" actualValue="9+" weight=".009" rank="4"/>
           <Attribute name="AGE" actualValue="28" weight=".006" rank="5"/>
    101790 <Details algorithm="Support Vector Machines" class="0">
           <Attribute name="COUNTRY_NAME" actualValue="Canada" weight=".068" rank="1"/>
           <Attribute name="HOUSEHOLD_SIZE" actualValue="4-5" weight=".018" rank="2"/>
           <Attribute name="EDUCATION" actualValue="7th-8th" weight=".015" rank="3"/>
           <Attribute name="CUST_GENDER" actualValue="F" weight=".013" rank="4"/>
           <Attribute name="AGE" actualValue="38" weight=".001" rank="5"/>

6.3.4 GROUPING Hint

Data mining functions consist of SQL functions such as PREDICTION*, CLUSTER*, FEATURE*, and ORA_DM_*. The GROUPING hint is an optional hint which applies to data mining scoring functions when scoring partitioned models.

Enhanced PREDICTION Function Command Format

This hint results in partitioning the input data set into distinct data slices so that each partition is scored in its entirety before advancing to the next partition. However, parallelism by partition is still available. Data slices are determined by the partitioning key columns used when the model was built. This method can be used with any data mining function against a partitioned model. The hint may yield a query performance gain when scoring large data that is associated with many partitions but may negatively impact performance when scoring large data with few partitions on large systems. Typically, there is no performance gain if you use the hint for single row queries.

<prediction function> ::=
    PREDICTION <left paren> /*+ GROUPING */ <prediction model>
        [ <comma> <class value> [ <comma> <top N> ] ]
        USING <mining attribute list> <right paren>

The syntax for only the PREDICTION function is given but it is applicable to any Data mining function where PREDICTION, CLUSTERING, and FEATURE_EXTRACTION scoring functions occur.

Example 6-11 Example

SELECT PREDICTION(/*+ GROUPING */my_model USING *) pred FROM <input table>;