Inverse MDS: Inferring dissimilarity structure from multiple item arrangements

The pairwise dissimilarities of a set of items can be intuitively visualized by a 2D arrangement of the items, in which the distances reflect the dissimilarities. Such an arrangement can be obtained by multidimensional scaling (MDS). We propose a method for the inverse process: inferring the pairwis...

Full description

Bibliographic Details
Main Authors: Nikolaus eKriegeskorte, Marieke eMur
Format: Article
Language:English
Published: Frontiers Media S.A. 2012-07-01
Series:Frontiers in Psychology
Subjects:
Online Access:http://journal.frontiersin.org/Journal/10.3389/fpsyg.2012.00245/full
_version_ 1818509439299223552
author Nikolaus eKriegeskorte
Marieke eMur
Marieke eMur
author_facet Nikolaus eKriegeskorte
Marieke eMur
Marieke eMur
author_sort Nikolaus eKriegeskorte
collection DOAJ
description The pairwise dissimilarities of a set of items can be intuitively visualized by a 2D arrangement of the items, in which the distances reflect the dissimilarities. Such an arrangement can be obtained by multidimensional scaling (MDS). We propose a method for the inverse process: inferring the pairwise dissimilarities from multiple 2-dimensional arrangements of items. Perceptual dissimilarities are classically measured using pairwise dissimilarity judgments. However, alternative methods including free sorting and 2D arrangements have previously been proposed. The present proposal is novel (a) in that the dissimilarity matrix is estimated by inverse MDS based on multiple arrangements of item subsets, and (b) in that the subsets are designed by an adaptive algorithm that aims to provide optimal evidence for the dissimilarity estimates. The subject arranges the items (represented as icons on a computer screen) by means of mouse drag-and-drop operations. The multi-arrangement method can be construed as a generalization of simpler methods: It reduces to pairwise dissimilarity judgments if each arrangement contains only two items, and to free sorting if the items are categorically arranged into discrete piles. Multi-arrangement combines the advantages of these methods. It is efficient (because the subject communicates many dissimilarity judgments with each mouse drag), psychologically attractive (because dissimilarities are judged in context), and can characterize continuous high-dimensional dissimilarity structures. We present two procedures for estimating the dissimilarity matrix: a simple weighted-aligned-average of the partial dissimilarity matrices and a computationally intensive algorithm, which estimates the dissimilarity matrix by iteratively minimizing the error of MDS-predictions of the subject’s arrangements. The Matlab code for interactive arrangement and dissimilarity estimation is available from the authors upon request.
first_indexed 2024-12-10T22:45:28Z
format Article
id doaj.art-db2a6b615eb94730b593f4872805a86a
institution Directory Open Access Journal
issn 1664-1078
language English
last_indexed 2024-12-10T22:45:28Z
publishDate 2012-07-01
publisher Frontiers Media S.A.
record_format Article
series Frontiers in Psychology
spelling doaj.art-db2a6b615eb94730b593f4872805a86a2022-12-22T01:30:36ZengFrontiers Media S.A.Frontiers in Psychology1664-10782012-07-01310.3389/fpsyg.2012.0024528167Inverse MDS: Inferring dissimilarity structure from multiple item arrangementsNikolaus eKriegeskorte0Marieke eMur1Marieke eMur2Medical Research Council Cognition and Brain Sciences UnitMedical Research Council Cognition and Brain Sciences UnitMaastricht UniversityThe pairwise dissimilarities of a set of items can be intuitively visualized by a 2D arrangement of the items, in which the distances reflect the dissimilarities. Such an arrangement can be obtained by multidimensional scaling (MDS). We propose a method for the inverse process: inferring the pairwise dissimilarities from multiple 2-dimensional arrangements of items. Perceptual dissimilarities are classically measured using pairwise dissimilarity judgments. However, alternative methods including free sorting and 2D arrangements have previously been proposed. The present proposal is novel (a) in that the dissimilarity matrix is estimated by inverse MDS based on multiple arrangements of item subsets, and (b) in that the subsets are designed by an adaptive algorithm that aims to provide optimal evidence for the dissimilarity estimates. The subject arranges the items (represented as icons on a computer screen) by means of mouse drag-and-drop operations. The multi-arrangement method can be construed as a generalization of simpler methods: It reduces to pairwise dissimilarity judgments if each arrangement contains only two items, and to free sorting if the items are categorically arranged into discrete piles. Multi-arrangement combines the advantages of these methods. It is efficient (because the subject communicates many dissimilarity judgments with each mouse drag), psychologically attractive (because dissimilarities are judged in context), and can characterize continuous high-dimensional dissimilarity structures. We present two procedures for estimating the dissimilarity matrix: a simple weighted-aligned-average of the partial dissimilarity matrices and a computationally intensive algorithm, which estimates the dissimilarity matrix by iteratively minimizing the error of MDS-predictions of the subject’s arrangements. The Matlab code for interactive arrangement and dissimilarity estimation is available from the authors upon request.http://journal.frontiersin.org/Journal/10.3389/fpsyg.2012.00245/fullrepresentationSimilaritymultidimensional scalingrepresentational similarity analysissimilarity judgment
spellingShingle Nikolaus eKriegeskorte
Marieke eMur
Marieke eMur
Inverse MDS: Inferring dissimilarity structure from multiple item arrangements
Frontiers in Psychology
representation
Similarity
multidimensional scaling
representational similarity analysis
similarity judgment
title Inverse MDS: Inferring dissimilarity structure from multiple item arrangements
title_full Inverse MDS: Inferring dissimilarity structure from multiple item arrangements
title_fullStr Inverse MDS: Inferring dissimilarity structure from multiple item arrangements
title_full_unstemmed Inverse MDS: Inferring dissimilarity structure from multiple item arrangements
title_short Inverse MDS: Inferring dissimilarity structure from multiple item arrangements
title_sort inverse mds inferring dissimilarity structure from multiple item arrangements
topic representation
Similarity
multidimensional scaling
representational similarity analysis
similarity judgment
url http://journal.frontiersin.org/Journal/10.3389/fpsyg.2012.00245/full
work_keys_str_mv AT nikolausekriegeskorte inversemdsinferringdissimilaritystructurefrommultipleitemarrangements
AT mariekeemur inversemdsinferringdissimilaritystructurefrommultipleitemarrangements
AT mariekeemur inversemdsinferringdissimilaritystructurefrommultipleitemarrangements