Questions tagged [multidimensional-scaling]

Technique that renders observed or computed (dis)similarities among objects into distances in a low-dimensional space (usually Euclidean). It thus constructs dimensions for the data; the objects can be plotted and conceptualized in those dimensions

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Finding the projection used in multidimensional scaling

Background I have a set of data points in high-dimensional (512D) space that I wish to map to 2D for visualisation. I am interested in observing in 2D the (approximate) relative distances between the ...
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Multidimensional scaling on distance or similarity matrix

Why doesn't the scatter plot change when I perform multidimensional scaling on distance or similarity matrix? This figure uses similarity matrix And this figure use distance matrix (sqrt(1-...
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Multidimensional scaling of random matrix

Suppose I have a random symmetric matrix W of size $n\times n$, with i.i.d. coefficients uniformly distributed in [0,1], and I set $W_{ii} = 0$. Then I apply a Multidimensional Scaling of dimension $...
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Individual differences scaling, additional investigations

I am learning individual differences scaling (AKA three-way multidimensional scaling) and I want to know what different ways there are to state that my results are reliable. I had to perform ...
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Sequential or dynamic multidimensional scaling

I am looking for a way to conduct sequential (dynamic) MDS based on several variables coded for a sequence of stimuli. Could anyone direct me to software for this purpose (especially R packages / code)...
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922 views

Normalizing data before applying MDS with strain criterion

The features of my dataset are like below: • BI-RADS assessment: 1 to 5 (ordinal) • Age: patient's age in years (integer) ...
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281 views

Is first dimension more informative in multidimensional scaling?

A property of Principal Components Analysis (PCA) is that the first dimension is the most informative, next the second and so on. Is this property true also for multidimensional scaling (MDS)?
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Non-metric multidimensional scaling with dichotomous independent variables?

I have a set of t-rflp fragment-length profiles from an investigation into microbial degradation of hydrocarbons as part of my undergrad dissertation. I want to study the effect of various variables ...
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RandomForest - MDS plot interpretation

I used randomForest to classify 6 animal behaviours (eg. Standing, Walking, Swimming etc.) based on 8 variables (different body postures and movement). The MDSplot in the randomForest package gives ...
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Computing and comparing semantic networks generated by grouped individuals

I have 2 groups, each containing 20 individuals. For each individual I have a dissimilarity matrix of a number of judged items. I'd like to evaluate whether there is an overall difference between the ...
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3answers
689 views

Metric and Clustering Method

I need some suggestions regarding what kind of metric and clustering analysis I should use. I read a lot of posts but didn't get any hints about this type of data. I have a 3000*5000 matrix, where ...
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123 views

Is a Biplot suitable ? Domestic Violence VS Non-Violence data

I have a small data set that consists solely of counts. I have several variables. For example State, for each state (Mexican States), for example, Tamauplipas I have the counts of domestic violence ...
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273 views

Methods of “Two-Way” Multidimensional Scaling (MDS)?

I just want to ask about the MDS. Below is the subcategory of the Multidimensional Scaling topic. Multidimensional Scaling Metric and Non-Metric Models Methods of "Two-Way" Multidimensional Scaling (...
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What is the role of MDS in modern statistics?

I recently came across multidimensional scaling. I am trying to understand this tool better and its role in modern statistics. So here are a few guiding questions: Which questions does it answer? ...
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Quantifying differences in a discrete distribution across several populations

Suppose you have a discrete random variable, $Y$, with a large number (say, $300$) of discrete (which happen to be nominal) possible outcomes. The mass function, $p(y)=P(Y=y)$, is unknown but a sample ...
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How to calculate the R-squared value and assess the model fit in multidimensional scaling?

I would like to do Multidimensional Scaling (MDS) using cmdscale() in R. I have read that it is useful to try out how many dimensions are suitable for the data by ...
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What's the difference between principal component analysis and multidimensional scaling?

How are PCA and classical MDS different? How about MDS versus nonmetric MDS? Is there a time when you would prefer one over the other? How do the interpretations differ?
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Interpretation of MDS factor plot

Suppose I run Multidimensional Scaling and I got the resulting plot. Can anybody suggest me how to interpret the plot. Please find one of my result below. Here I've 5 concepts which I run the MDS ...
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Visualizing multi-dimensional data (LSI) in 2D

I'm using latent semantic indexing to find similarities between documents (thanks, JMS!) After dimension reduction, I've tried k-means clustering to group the documents into clusters, which works ...
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Big-O Scaling of R's cmdscale()

I'm trying to run R's multidimensional scaling algorithm, cmdscale, on roughly 2,200 variables, i.e. a 2,200x2,200 distance matrix. It's taking forever (about a ...
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Multidimensional scaling pseudo-code

I am planning to write a program that performs MDS. Any pointers to where I can access the pseudo-code for MDS? Thanks!
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Adding labels to points using mds and scatter3d package with R

I have a dataset forwhich i have performed an mds and visualized the results using scatterplot3d library. However i would like to see the names of the points on the 3d plot. How do i accomplish that? ...
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Help me understand nMDS algorithm

I have been reading Zuur, Ieno and Smith (2007) Analyzing ecological data, and on page 262, they try to explain how nMDS (non-metric multidimensional scaling) algorithm works. As my background is in ...