skcriteria.agg.ram module

RAM (Root Assessment Method) decision-making method.

skcriteria.agg.ram.ram(matrix, objectives, weights)

Execute RAM without any validation.

class skcriteria.agg.ram.RAM

Bases: SKCDecisionMakerABC

Root Assessment Method (RAM).

RAM calculates the utility value of each alternative by aggregating their scores over the criteria, treating beneficial and non-beneficial criteria differently. The method uses an aggregation function that combines compensatory and partially compensatory characteristics.

The aggregation function used is:

\[RI_i = \sqrt[2 + S_{-i}]{2 + S_{+i}}\]

where \(S_{+i}\) is the weighted sum of beneficial criteria for alternative \(i\), \(S_{-i}\) is the weighted sum of non-beneficial criteria for alternative \(i\). \(RI_i\) is the score of alternative \(i\) based on the RAM method. The ranking is done based on the score, where higher scores indicate better alternatives.

To use this method, the decision matrix should be normalized using the following formula:

\[\overline{X}_{ij} = \frac{X_{ij}}{\sum\limits_{j=1}^m X_{ij}}\]

References

[Sotoudeh-Anvari, 2023]