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honeyasha
Contributor III
Contributor III

What is the difference between Subset ratio and information density.

Can any one explain me the difference between Subset ratio and information density with example.

5 Replies
jonathandienst
Partner - Champion III
Partner - Champion III

Information density is the % of non-null values in the table

Subset ratio applies to key fields (those that exist in more than one table) and is the % of the distinct values of the field in the table of the total distinct values of the field in all tables that contain that field.

Logic will get you from a to b. Imagination will take you everywhere. - A Einstein
arvind1494
Specialist
Specialist

Information density:

Percentage of non-null rows in a field.

suppose field country has total 10 Records but 2 records are null then

theiw are 8 non-null values

so information density = 80 %.

Subset Ratio:

It is the ratio of distinct non-null values in a field to the total distinct non- null values in that field in entire data model

suppose table A has field country and 10 records are their

in table B country has 20 records but all records are distinct to the country field in table A

Now Subset ratio of Country in table A =distinct non - null values in country in table A / [distinct non - null values in  country in table A + distinct non - null values in country in table B]

= 10/ [10+20]

=10/30

=33.33%

wilsonwebb
Partner - Contributor III
Partner - Contributor III

Hi Rohini,

you can also view the below link.

information density and subset ratio? What is the use of this?

sujan24s
Contributor III
Contributor III

Information density : OF the field, which indicates the percentage of rows that contain a non-null value.

Subset ratio: which shows the percentage of all distinct values for a field in the table compared to all the distinct values for that field in the entire data model. It is only relevant for key fields since they are present in multiple tables and do not all share the same value. Subset ratios can be used to easily spot problems in key field associations. For example, when the combined total of subset ratios for multiple tables is 100 percent, this may indicate that there are no matching keys between these tables.