Help with question answer I believe it's wrong answered

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#1

Screen Link:

optimize a model

in the question :
Which of the following statements are correct about cardinality?

My answer was :

Unique count is high > high level of cardinality
Distinct count is low > low level of cardinality

according to this screenshot from Microsoft learn :

asnwer
asnwer1112×195 14.4 KB

Optimize a model from MS Learn

What actually happened:
the second choice was considered wrong and this one is selected as the right answer

Distinct count is high > low level of cardinality

which isn’t right according to MS learn reference attached

1 Like
#2

Hi Samas,

Agreed, that’s weird. I’ve understood cardinality as just the amount of value options a column can have. High cardinality means many value options and low cardinality means few value options. This is the first I’m hearing of cardinality being related to values that only appear once. I’ll be interested to see if anyone else can shed some light on this.

The description used here are also is a bit confusing, as distinct and unique are very close in definition, debatably they are synonyms. The syntax is also confusing, is the ‘>’ character supposed to be an ‘=’ sign?

#3

yes the two definitions are very near and confusing but here’s the difference between them:

Distinct count means the number of unique values in the dataset regardless their time of occurrences
Unique count means how many values appear once