ahp v2.4.2

ahp.js

This node.js module is a library for Analytic Hierarchy Process(AHP).

Wiki page for AHP: https://en.wikipedia.org/wiki/Analytic_hierarchy_process

Project page

• Github
• NPM

Glossary

Install

$ npm i ahp

Quick Samples

Hello World Sample

import AHP from 'ahp';
const ahpContext = new AHP();

ahpContext.addItems(['VendorA', 'VendorB', 'VendorC']);

ahpContext.addCriteria(['price', 'functionality', 'UX']);

//rank criteria with rank scale
ahpContext.rankCriteriaItem('price', [
    ['VendorB', 'VendorC', 1 / 2],
    ['VendorA', 'VendorC', 1 / 2],
    ['VendorA', 'VendorB', 1]
]);

//rank criteria with rank scale
ahpContext.rankCriteriaItem('functionality', [
    ['VendorB', 'VendorC', 1],
    ['VendorA', 'VendorC', 5],
    ['VendorA', 'VendorB', 5]
]);

//rank criteria with absolute rank scole
ahpContext.setCriteriaItemRankByGivenScores('UX', [10, 10, 1]);

ahpContext.rankCriteria(
    [
        ['price', 'functionality', 3],
        ['price', 'UX', 3],
        ['functionality', 'UX', 1]
    ]
);

const output = ahpContext.run();
console.log(output);

Console output

{ error: null,
  rankingMatrix:
   [ [ 0.25, 0.7142857142857141, 0.4761904761904761 ],
     [ 0.25, 0.14285714285714285, 0.4761904761904761 ],
     [ 0.5, 0.14285714285714285, 0.047619047619047616 ] ],
  itemRankMetaMap:
   { price: { ci: 0, ri: 0.58, cr: 0 },
     functionality: { ci: 0, ri: 0.58, cr: 0 },
     UX: { ci: 0, ri: 0.58, cr: 0 } },
  criteriaRankMetaMap:
   { ci: 0,
     ri: 0.58,
     cr: 0,
     weightedVector: [ 0.6000000000000001, 0.20000000000000004, 0.20000000000000004 ] },
  rankedScoreMap:
   { VendorA: 0.3880952380952381,
     VendorB: 0.27380952380952384,
     VendorC: 0.33809523809523817 },
  rankedScores: [ 0.3880952380952381, 0.27380952380952384, 0.33809523809523817 ] }

Import Data Context Sample

import AHP from 'ahp';

const ahpContext = new AHP();

/*
notice that in this demo, we import price item ranking with matrix,
and import UX item ranking with absolute scores. Both are supported.
*/
ahpContext.import({
    items: ['VendorA', 'VendorB', 'VendorC'],
    criteria: ['price', 'functionality', 'UX'],
    criteriaItemRank: {
        price: [
            [1, 1, 0.5],
            [1, 1, 0.5],
            [2, 2, 1]
        ],
        functionality: [
            [1, 5, 5],
            [0.2, 1, 1],
            [0.2, 1, 1]
        ],
        UX: [10, 10, 1]
    },
    criteriaRank: [
        [1, 3, 3],
        [0.3333333333333333, 1, 1],
        [0.3333333333333333, 1, 1]
    ]
});

const output = ahpContext.run();
console.log(output);

Console output

{ error: null,
  rankingMatrix:
   [ [ 0.25, 0.7142857142857141, 0.4761904761904761 ],
     [ 0.25, 0.14285714285714285, 0.4761904761904761 ],
     [ 0.5, 0.14285714285714285, 0.047619047619047616 ] ],
  itemRankMetaMap:
   { price: { ci: 0, ri: 0.58, cr: 0 },
     functionality: { ci: 0, ri: 0.58, cr: 0 },
     UX: { ci: 0, ri: 0.58, cr: 0 } },
  criteriaRankMetaMap:
   { ci: 0,
     ri: 0.58,
     cr: 0,
     weightedVector: [ 0.6000000000000001, 0.20000000000000004, 0.20000000000000004 ] },
  rankedScoreMap:
   { VendorA: 0.3880952380952381,
     VendorB: 0.27380952380952384,
     VendorC: 0.33809523809523817 },
  rankedScores: [ 0.3880952380952381, 0.27380952380952384, 0.33809523809523817 ] }

Export Data Context Sample

import AHP from 'ahp';
const ahpContext = new AHP();
......
const util = require('util');
console.log(util.inspect(ahpContext.export(), false, null));

Console output

{ items: [ 'VendorA', 'VendorB', 'VendorC' ],
  criteria: [ 'price', 'functionality', 'UX' ],
  criteriaItemRank:
   { price: [ [ 1, 1, 0.5 ], [ 1, 1, 0.5 ], [ 2, 2, 1 ] ],
     functionality: [ [ 1, 5, 5 ], [ 0.2, 1, 1 ], [ 0.2, 1, 1 ] ],
     UX: [ [ 1, 1, 10 ], [ 1, 1, 10 ], [ 0.1, 0.1, 1 ] ] },
  criteriaRank:
   [ [ 1, 3, 3 ],
     [ 0.3333333333333333, 1, 1 ],
     [ 0.3333333333333333, 1, 1 ] ] }

Output Analysis Process Information Sample

import AHP from 'ahp';
const ahpContext = new AHP();
......
const analyticContext = ahpContext.debug();
for(const key in analyticContext){
    console.log(`${key}: `, analyticContext[key], '\n');
}

Console output

error:  null

rankingMatrix:  [ [ 0.25, 0.7142857142857141, 0.4761904761904761 ],
  [ 0.25, 0.14285714285714285, 0.4761904761904761 ],
  [ 0.5, 0.14285714285714285, 0.047619047619047616 ] ]

itemRankMetaMap:  { price: { ci: 0, ri: 0.58, cr: 0 },
  functionality: { ci: 0, ri: 0.58, cr: 0 },
  UX: { ci: 0, ri: 0.58, cr: 0 } }

criteriaRankMetaMap:  { ci: 0,
  ri: 0.58,
  cr: 0,
  weightedVector: [ 0.6000000000000001, 0.20000000000000004, 0.20000000000000004 ] }

rankedScoreMap:  { VendorA: 0.3880952380952381,
  VendorB: 0.27380952380952384,
  VendorC: 0.33809523809523817 }

rankedScores:  [ 0.3880952380952381, 0.27380952380952384, 0.33809523809523817 ]

log:  ==========================================
context:
items:
[ 'VendorA', 'VendorB', 'VendorC' ]
criteria:
[ 'price', 'functionality', 'UX' ]
criteriaItemRank:
{ price: [ [ 1, 1, 0.5 ], [ 1, 1, 0.5 ], [ 2, 2, 1 ] ],
  functionality: [ [ 1, 5, 5 ], [ 0.2, 1, 1 ], [ 0.2, 1, 1 ] ],
  UX: [ [ 1, 1, 10 ], [ 1, 1, 10 ], [ 0.1, 0.1, 1 ] ] }
criteriaRank:
[ [ 1, 3, 3 ],
  [ 0.3333333333333333, 1, 1 ],
  [ 0.3333333333333333, 1, 1 ] ]
__________________________________
criteriaItemRank['price']
---------------------------------------------
|          |   VendorA|   VendorB|   VendorC|
|----------|----------|----------|----------|
|   VendorA|     1.000|     1.000|     0.500|
|   VendorB|     1.000|     1.000|     0.500|
|   VendorC|     2.000|     2.000|     1.000|
---------------------------------------------

Consistentcy index: 0
Random index: 0.58
Consistentcy ratio: 0
CR<=0.1 => sufficient consistency
__________________________________
criteriaItemRank['functionality']
---------------------------------------------
|          |   VendorA|   VendorB|   VendorC|
|----------|----------|----------|----------|
|   VendorA|     1.000|     5.000|     5.000|
|   VendorB|     0.200|     1.000|     1.000|
|   VendorC|     0.200|     1.000|     1.000|
---------------------------------------------

Consistentcy index: 0
Random index: 0.58
Consistentcy ratio: 0
CR<=0.1 => sufficient consistency
__________________________________
criteriaItemRank['UX']
---------------------------------------------
|          |   VendorA|   VendorB|   VendorC|
|----------|----------|----------|----------|
|   VendorA|     1.000|     1.000|    10.000|
|   VendorB|     1.000|     1.000|    10.000|
|   VendorC|     0.100|     0.100|     1.000|
---------------------------------------------

Consistentcy index: 0
Random index: 0.58
Consistentcy ratio: 0
CR<=0.1 => sufficient consistency
__________________________________
criteriaRank:
---------------------------------------------------------
|             |        price|functionality|           UX|
|-------------|-------------|-------------|-------------|
|        price|        1.000|        3.000|        3.000|
|functionality|        0.333|        1.000|        1.000|
|           UX|        0.333|        1.000|        1.000|
---------------------------------------------------------

Consistentcy index: 0
Random index: 0.58
Consistentcy ratio: 0
CR<=0.1 => sufficient consistency
Criteria Weight Vector: 0.6000000000000001,0.20000000000000004,0.20000000000000004
__________________________________

rankingMatrix: (Higher score is better)
---------------------------------------
|             |VendorA|VendorB|VendorC|
|-------------|-------|-------|-------|
|        price|  0.250|  0.250|  0.500|
|functionality|  0.714|  0.143|  0.143|
|           UX|  0.476|  0.476|  0.048|
---------------------------------------

__________________________________
ranked item scores: (Higher score is better)
---------------
|       |Score|
|-------|-----|
|VendorA|0.388|
|VendorB|0.274|
|VendorC|0.338|
---------------

==========================================

API

• ahp.js
  • Project page
  • Glossary
  • Install
  • Quick Samples
    • Hello World Sample
    • Import Data Context Sample
    • Export Data Context Sample
    • Output Analysis Process Information Sample
  • API
    • import(context)
    • export()
    • addItem(item)
    • addItems(items)
    • removeItem(item)
    • removeItems(items)
    • addCriterion(criterion)
    • addCriteria(criteria)
    • removeCriterion(criterion)
    • removeCriteria(criteria)
    • rankCriteria(preferences)
    • setCriteriaRankByGivenScores(vector)
    • rankCriteriaItem(criterion, preferences)
    • setCriteriaItemRankByGivenScores(criterion, vector)
    • resetCriteriaItemRank(criteria)
    • resetCriteriaRank()
    • findNextProblem()
    • debug()
    • run()
  • Classes
    • AHP
    • ContextError
    • NoItem
    • NoCriteria
    • MissingCriteriaItemRank
    • MissingCriteriaRank
    • CriteriaItemRankInsufficientConsistencyRatio
    • CriteriaRankInsufficientConsistencyRatio
  • Arthor contact

import(context)

Description:

Importing context from JSON

Parameters:

Return:

Example:

ahpContext.import({
    items: ['Vendor A', 'Vendor B', 'Vendor C'],
    criteria: ['price', 'functionality', 'UX'],
    criteriaItemRank:
    {
        price: [[1, 1, 0.5], [1, 1, 0.5], [2, 2, 1]],
        functionality: [[1, 1, 5], [1, 1, 5], [0.2, 0.2, 1]],
        UX: [[1, 1, 10], [1, 1, 10], [0.1, 0.1, 1]]
    },
    criteriaRank:
    [[1, 3, 3],
    [0.3333333333333333, 1, 1],
    [0.3333333333333333, 1, 1]]
});

export()

Description:

Exporting context as JSON

Parameters:

nil

Return:

Example:

ahpContext.export();

addItem(item)

Description:

Adding Item

Parameters:

Return:

Example:

ahpContext.addItem('Vendor A');

addItems(items)

Description:

Adding Items

Parameters:

Return:

Example:

ahpContext.addItems(['Vendor A', 'Vendor B', 'Vendor C']);

removeItem(item)

Description:

Removing Item

Parameters:

Return:

Example:

ahpContext.removeItem('Vendor A');

removeItems(items)

Description:

Removing Items

Parameters:

Return:

Example:

ahpContext.removeItems(['Vendor A', 'Vendor B', 'Vendor C']);

addCriterion(criterion)

Description:

Adding criterion

Parameters:

Return:

Example:

ahpContext.addCriterion('price');

addCriteria(criteria)

Description:

Adding criteria

Parameters:

Return:

Example:

ahpContext.addCriteria(['price', 'functionality', 'UX']);

removeCriterion(criterion)

Description:

Removing criterion

Parameters:

Return:

Example:

ahpContext.removeCriterion('price');

removeCriteria(criteria)

Description:

Removing criteria

Parameters:

Return:

Example:

ahpContext.removeCriteria(['price', 'functionality', 'UX']);

rankCriteria(preferences)

Description:

Ranking criteria

Parameters:

Return:

Example:

ahpContext.rankCriteria(
    [
        {preferredCriterion: 'price', comparingCriterion: 'functionality', scale:3},
        {preferredCriterion: 'price', comparingCriterion: 'UX', scale:3},
        {preferredCriterion: 'functionality', comparingCriterion: 'UX', scale:1}
    ]
);

//or
ahpContext.rankCriteria(
    [
        ['price', 'functionality', 3],
        ['price', 'UX', 3],
        ['functionality', 'UX', 1]
    ]
);

setCriteriaRankByGivenScores(vector)

Description:

Ranking criteria by Given Scores. This is suitable for the use case which you want to directly define the criteria ranking scores.

Parameters:

Return:

Example:

//assume criteria = ['price', 'functionality', 'UX'];

ahpContext.setCriteriaRankByGivenScores([1, 2, 5]);
// is equivalent to
ahpContext.rankCriteria(
    [
        ['price', 'functionality', 1/2],
        ['price', 'UX', 1/5],
        ['functionality', 'UX', 2/5]
    ]
);

rankCriteriaItem(criterion, preferences)

Description:

Rank Criteria perspective Item

Parameters:

Return:

Example:

ahpContext.rankCriteriaItem('price', [
    {preferredItem:'VendorB', comparingItem:'VendorC', scale:1 / 2},
    {preferredItem:'VendorA', comparingItem:'VendorC', scale:1 / 2},
    {preferredItem:'VendorA', comparingItem:'VendorB', scale:1}
]);

//or
ahpContext.rankCriteriaItem('price', [
    ['VendorB', 'VendorC', 1 / 2],
    ['VendorA', 'VendorC', 1 / 2],
    ['VendorA', 'VendorB', 1]
]);

setCriteriaItemRankByGivenScores(criterion, vector)

Description:

Base on specific criterion to rank items by Given Scores. This is suitable for the use case which you want to directly define the criteria perspective item ranking scores.

Parameters:

Return:

Example:

ahpContext.setCriteriaItemRankByGivenScores('price', [10, 5, 7]);

// is equivalent to
ahpContext.rankCriteriaItem(
    'price',
    [
        ['Vendor A', 'Vendor B', 10/5],
        ['Vendor A', 'Vendor C', 10/7],
        ['Vendor B', 'Vendor C', 5/7]
    ]
);

resetCriteriaItemRank(criteria)

Description:

Reset Criteria perspective Item ranking matrix.

Parameters:

Return:

Example:

ahpContext.resetCriteriaItemRank(['price', 'functionality']);

resetCriteriaRank()

Description:

Reset Criteria ranking matrix.

Parameters:

nil

Return:

Example:

ahpContext.resetCriteriaRank();

findNextProblem()

Description:

Auto check whether the existing input context can successfully done the AHP analysis process. If there are missing information or data inconsistency, this function would return the Error it found.

Parameters:

nil

Return:

Example:

let problem = ahpContext.findNextProblem();

debug()

Description:

Try to run the AHP analysis process. The result information and the debug log output will be returned.

Parameters:

nil

Return Object properties:

Example:

......
let analyticContext = ahpContext.debug();
for(let key in analyticContext){
    console.log(`${key}: `, analyticContext[key], '\n');
}

Console output

error:
 null

rankingMatrix:
 [ [ 0.25, 0.7142857142857141, 0.4761904761904761 ],
  [ 0.25, 0.14285714285714285, 0.4761904761904761 ],
  [ 0.5, 0.14285714285714285, 0.047619047619047616 ] ]

itemRankMetaMap:
 { price: { ci: 0, ri: 0.58, cr: 0 },
  functionality: { ci: 0, ri: 0.58, cr: 0 },
  UX: { ci: 0, ri: 0.58, cr: 0 } }

criteriaRankMetaMap:
 { ci: 0,
  ri: 0.58,
  cr: 0,
  weightedVector: [ 0.6000000000000001, 0.20000000000000004, 0.20000000000000004 ] }

rankedScoreMap:
 { VendorA: 0.3880952380952381,
  VendorB: 0.27380952380952384,
  VendorC: 0.33809523809523817 }

log:
 ==========================================
context:
items:
[ 'VendorA', 'VendorB', 'VendorC' ]
criteria:
[ 'price', 'functionality', 'UX' ]
criteriaItemRank:
{ price: [ [ 1, 1, 0.5 ], [ 1, 1, 0.5 ], [ 2, 2, 1 ] ],
  functionality: [ [ 1, 5, 5 ], [ 0.2, 1, 1 ], [ 0.2, 1, 1 ] ],
  UX: [ [ 1, 1, 10 ], [ 1, 1, 10 ], [ 0.1, 0.1, 1 ] ] }
criteriaRank:
[ [ 1, 3, 3 ],
  [ 0.3333333333333333, 1, 1 ],
  [ 0.3333333333333333, 1, 1 ] ]
__________________________________
criteriaItemRank['price']
---------------------------------------------
|          |   VendorA|   VendorB|   VendorC|
|----------|----------|----------|----------|
|   VendorA|     1.000|     1.000|     0.500|
|   VendorB|     1.000|     1.000|     0.500|
|   VendorC|     2.000|     2.000|     1.000|
---------------------------------------------

Consistentcy index: 0
Consistentcy ratio: 0
CR<=0.1 => sufficient consistency
__________________________________
criteriaItemRank['functionality']
---------------------------------------------
|          |   VendorA|   VendorB|   VendorC|
|----------|----------|----------|----------|
|   VendorA|     1.000|     5.000|     5.000|
|   VendorB|     0.200|     1.000|     1.000|
|   VendorC|     0.200|     1.000|     1.000|
---------------------------------------------

Consistentcy index: 0
Consistentcy ratio: 0
CR<=0.1 => sufficient consistency
__________________________________
criteriaItemRank['UX']
---------------------------------------------
|          |   VendorA|   VendorB|   VendorC|
|----------|----------|----------|----------|
|   VendorA|     1.000|     1.000|    10.000|
|   VendorB|     1.000|     1.000|    10.000|
|   VendorC|     0.100|     0.100|     1.000|
---------------------------------------------

Consistentcy index: 0
Consistentcy ratio: 0
CR<=0.1 => sufficient consistency
__________________________________
criteriaRank:
---------------------------------------------------------
|             |        price|functionality|           UX|
|-------------|-------------|-------------|-------------|
|        price|        1.000|        3.000|        3.000|
|functionality|        0.333|        1.000|        1.000|
|           UX|        0.333|        1.000|        1.000|
---------------------------------------------------------

Consistentcy index: 0
Consistentcy ratio: 0
CR<=0.1 => sufficient consistency
Criteria Weight Vector: 0.6000000000000001,0.20000000000000004,0.20000000000000004
__________________________________

rankingMatrix: (Higher score is better)
---------------------------------------
|             |VendorA|VendorB|VendorC|
|-------------|-------|-------|-------|
|        price|  0.250|  0.250|  0.500|
|functionality|  0.714|  0.143|  0.143|
|           UX|  0.476|  0.476|  0.048|
---------------------------------------

__________________________________
ranked item scores: (Higher score is better)
---------------
|       |Score|
|-------|-----|
|VendorA|0.388|
|VendorB|0.274|
|VendorC|0.338|
---------------

==========================================

run()

Description:

Try to run the AHP analysis process. The result information will be returned.

Parameters:

nil

Return Object properties:

Example:

......
let analyticContext = ahpContext.run();
for(let key in analyticContext){
    console.log(`${key}: `, analyticContext[key], '\n');
}

Console output

error:
 null

rankingMatrix:
 [ [ 0.25, 0.7142857142857141, 0.4761904761904761 ],
  [ 0.25, 0.14285714285714285, 0.4761904761904761 ],
  [ 0.5, 0.14285714285714285, 0.047619047619047616 ] ]

itemRankMetaMap:
 { price: { ci: 0, ri: 0.58, cr: 0 },
  functionality: { ci: 0, ri: 0.58, cr: 0 },
  UX: { ci: 0, ri: 0.58, cr: 0 } }

criteriaRankMetaMap:
 { ci: 0,
  ri: 0.58,
  cr: 0,
  weightedVector: [ 0.6000000000000001, 0.20000000000000004, 0.20000000000000004 ] }

rankedScoreMap:
 { VendorA: 0.3880952380952381,
  VendorB: 0.27380952380952384,
  VendorC: 0.33809523809523817 }

Classes

AHP

Description

The AHP context class for input items, criteria & rankings. And then run the AHP process.

API Functions:

• API functions

ContextError

Description

The abstract base context error object.

Function:

• toQuestion(): Return the text representation of the Error followup message.

NoItem

Description

There are no items defined.

Preperties

NoCriteria

Description

There are no criteria defined.

Preperties

MissingCriteriaItemRank

Description

Some item ranking information is not yet input.

Preperties

MissingCriteriaRank

Description

Some criteria ranking information is not yet input.

Preperties

CriteriaItemRankInsufficientConsistencyRatio

Description

The consistency ratio for item ranking calculated is inconsistent(>0.1).

Preperties

CriteriaRankInsufficientConsistencyRatio

Description

The consistency ratio for criteria ranking calculated is inconsistent(>0.1).

Preperties

Arthor contact

• Eric Yu: airic.yu@gmail.com