Enter the number of true positives, false negatives, and false positives into the calculator to determine the Effectiveness Index.

Effectiveness Index Formula

The following formula is used to calculate the Effectiveness Index.

EI = (TP / (TP + FN)) * (TP / (TP + FP))

Variables:

  • EI is the Effectiveness Index
  • TP is the number of true positives
  • FN is the number of false negatives
  • FP is the number of false positives

To calculate the Effectiveness Index, divide the number of true positives by the sum of true positives and false negatives. Then, divide the number of true positives by the sum of true positives and false positives. Multiply these two results together to get the Effectiveness Index.

What is an Effectiveness Index?

An Effectiveness Index is a quantitative measure used to evaluate the efficiency or productivity of a particular system, process, or individual. It is often used in business and management to assess the performance of employees, departments, or entire organizations. The index is typically calculated by comparing actual outcomes to expected or desired outcomes, and can be used to identify areas for improvement, track progress over time, and make informed decisions about resource allocation.

How to Calculate Effectiveness Index?

The following steps outline how to calculate the Effectiveness Index.


  1. First, determine the number of true positives (TP).
  2. Next, determine the number of false negatives (FN).
  3. Next, determine the number of false positives (FP).
  4. Next, gather the formula from above = EI = (TP / (TP + FN)) * (TP / (TP + FP)).
  5. Finally, calculate the Effectiveness Index.
  6. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

TP: number of true positives = 50

FN: number of false negatives = 10

FP: number of false positives = 5