TD_CFilter Output - Analytics Database

Database Analytic Functions

Deployment
VantageCloud
VantageCore
Edition
Enterprise
IntelliFlex
VMware
Product
Analytics Database
Release Number
17.20
Published
June 2022
ft:locale
en-US
ft:lastEdition
2025-04-01
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jmh1512506877710
Product Category
Teradata Vantageā„¢
Column Name Data Type Description
partition_column ANY Column to copy to output table. Used to partition input data and output table.
TD_item1 VARCHAR Name of item1.
TD_item2 VARCHAR Name of item2.
cntb INTEGER Count of co-occurrence of both items in partition.
cnt1 INTEGER Count of occurrence of item1 in partition.
cnt2 INTEGER Count of occurrence of item2 in partition.
score REAL Product of two conditional probabilities:

P({ item2 | item1 }) * P({ item1 | item2 })

Preceding product equals following quotient:

(cntb * cntb)/(cnt1 * cnt2)

support REAL

Percentage of transactions in partition in which the two items co-occur, calculated with this formula:

cntb/tran_cnt

where tran_cnt is the number of transactions in the partition.

confidence REAL Percentage of transactions in partition in which item1 occurs, in which item2 also occurs, calculated with this formula:

cntb/cnt1

lift REAL Ratio of observed support value to expected support value if item1 and item2 were independent; that is:

support(item1 and item2) / [support(item1) * support(item2)]

Value is calculated with this formula:

(cntb/tran_cnt) / [(cnt1/tran_cnt) * (cnt2/tran_cnt)]

If lift > 1, the occurrence of item1 or item2 has a positive effect on the occurrence of the other items.

If lift = 1, the occurrence of item1 or item2 has a no effect on the occurrence of the other items.

If lift < 1, the occurrence of item1 or item2 has a negative effect on the occurrence of the other items.

z_score REAL Significance of co-occurrence, assuming that cntb follows a normal distribution, calculated with this formula:

(cntb - mean(cntb)) / sd(cntb)

If all cntb values are equal, then sd(cntb) is 0, and function does not calculate zscore.