L4; Ideal Point Mehods

Question 1

Ideal Point Methods

Answer 1

assess alternatives on the basis of their separation from an ideal point.
Two most prominent ideal point methods are
TOPSIS (technique for order preference by similarity to ideal solutions)
VIKOR( multi-criteria optimisation and compromise solution)

Question 2

differences between TOPSIS and VIKOR

Answer 2

different normalisation procedures

different aggregating function

Question 3

TOPSIS

Answer 3

the principle behind TOPSIS is that the optimal alternative should have the shortest distance from the positive ideal solution and the furthest distance from the negative ideal solution.
The positive and negative ideal solutions are artificial alternatives which are hypothesised by the decision-maker, based on the ideal solution for all criteria and the worst solution which possesses the most inferior decision variables.
TOPSIS calculates the results by comparing EUCLIDEAN distances between the actual alternatives and the hypothesised ones.

Question 4

types of distance

Answer 4

1. Euclidean distance is the distance between two points that you would measure with a ruler. (a straight between two points)
2. Manhattan distance is measured by drawing a mix of horizontal and vertical lines between two points.
3. Chebychev is measured by choosing the longest line on either horizontal and vertical.

Question 5

function of TOPSIS

Answer 5

=SQRT(SUMSQ( ; )

Question 6

limitation of TOPSIS/ VIKOR

Answer 6

suffer from the rank reversal problem like AHP