How to find the type of association between the attributes?

Question:

How to find the type of association between the attributes when N = 180; (A) = 160, (β) = 130 and (αβ) = 6.


Solution:

Step 1: Prepare a 9 square table.

B

β

Total

A

36

124

160

α

14

6

20

Total

50

​130

180

Step 2: Using comparison method we note (AB) = 36

Step 3: [(A) x (B)] / N = [160 x 50] / 180 = 44.44


Answer:

Since (AB) < [(A) x (B)] / N, we can say the attributes are negatively associated.


Concept:

  • Association of Attributes can be Positive or Negative. When the presence of one attribute is associated with the absence of the other attribute then the attributes are negatively associated.

  • Using Comparison Method -

  1. Attributes are independent when (AB) = (A) x (B) / N

  2. Attributes are positively associated when (AB) > (A) x (B) / N

  3. Attributes are negatively associated when (AB) < (A) x (B) / N


Video Solution:


How to find the type of association between the attributes with a Solved Example from Theory of Attributes