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4 votes
1 answer
431 views

Cluster analysis without knowing the structure of the data set

I’m working on a task regarding cluster analysis for about half a year now, but since the fields of pattern recognition and cluster analysis are quite complex ones, I would call myself a beginner in ...
0 votes
0 answers
245 views

Streaming K-medoids

Mahout, Hadoop machine learning library, contains an implementation of Streaming K-means algorithm that is based on the following paperworks The Effectiveness of Lloyd-Type Methods for the k-Means ...
3 votes
0 answers
410 views

When to use K-Medoids instead of K-means

When it's better to use K-Medoids rather than K-Means? Can anybody give some examples of dataset for the same?
3 votes
1 answer
2k views

Assign new data to a cluster (using Gower distance and PAM algorithm)

I have a dataset which has mixed data types and hence I used Gower dissimilarity matrix as input to cluster the data using Partitioning Around Medoids (PAM) algorithm. I wanted to know if there is any ...
5 votes
1 answer
1k views

Can silhouette be calculated with distances to centroids, instead of pairwise point distances?

I am using Silhouette cluster validation for each repetition (for a specific K) of k-means, k-modes and k-medoids. All the definitions of Silhouette I see calculate the distance of each point to ...
1 vote
0 answers
318 views

Deterministic Methods to Initialize K-Means and K-Medoids Clustering Methods

I am looking for effective and deterministic methods to initialize K-Means and K-Medoids algorithms. There is a great answer in Methods of initializing K-Means Clustering yet most of them has some ...
10 votes
2 answers
25k views

What is the benefit of using Manhattan distance for K-medoid than using Euclidean distance?

Please give me the reasons. I didn't find any k-medoid example that's calculation is done using Euclidean distance. All examples are made of Manhattan distance for k-medoid.
1 vote
1 answer
113 views

Understanding PAM - why is it greedy?

I've been studying k-medoids for a while but i can't understand the first step or BUILD step: in particular i can't get how the initial medoids would be "greedy". I'm not much confident with the ...
1 vote
0 answers
358 views

How to compare clustering algorithms of numerical and nominal data

I have a dataset for clustering including numerical and nominal variables. I would like to compare the k-means and k-medoids clustering algorithms and I would also like to find the optimal k-value (...
4 votes
3 answers
4k views

Clustering based on large Jensen-Shannon Divergence distance matrix

I have a dataset with large number of features and about 15 000 observations. I’m using a probability distribution distance metric related to Jensen-Shannon divergence (JSD) to cluster the ...
0 votes
1 answer
2k views

How to select a single updated centroid if multiple centroids are equidistant for a single group when running k-means/k-medoids?

I am trying to write my own k-means and k-medoids clustering algorithms. I understand the general idea: given k centroids, one continually updates the centroids ...
1 vote
0 answers
107 views

Graph clustering for balanced sum of absolute deviations within each cluster (same sum of intracluster distances)

I'm given a set of points and a distance matrix. With these I'm trying to develop an algorithm similar to k-means that tries to minimize the sum of distances from each cluster datapoint to it's center ...
0 votes
2 answers
1k views

Clustering Categorical Data

I want to cluster a data set where all variables are categorical. Which would be more effective for doing so, k - means or k - medoids? The data set is linked below. https://archive.ics.uci.edu/...
-1 votes
2 answers
647 views

how to classify input image using clustering algorithm such as k-mean?

I want to classify cifar10 images using a clustering algorithm (k-mean). Each image in the cifar10 dataset has a label, so, the results must be a set of labels which are corresponding to the test ...
2 votes
1 answer
1k views

K-means++ like initialization for K-medoids

Does it make sense to use initialization in K-medoids like in the case of K-means++? To be precise - is it good to select "farthest" points as initial medoids? (farthest in sense that points that are ...
4 votes
1 answer
717 views

Why use K-medoids for sequence analysis?

In the package WeightedCluster there seems to be facilities for using K-medoids clustering (i.e. wcKMedoids()), but not the more ...
2 votes
1 answer
61 views

Covering 2D data by m squares (alternative to k-means)

Let us have some data $x_i\in\mathbb{R}^2$ for $i=1,\dots,n$. Let $m=1000$. Let a small number is given, e.g. $m=5$. The goals is to cover $n$ data by $m$ squares of the same size. The size shall be ...
1 vote
1 answer
3k views

Silhouette value after normalizing a variable and re-clustering

I have a non-normalized variable and other normalized variables and I make a clustering with k medoids (or k means). If I let the first variable non-normalized, I get better results in terms of ...
1 vote
1 answer
412 views

Clustering issues

I have a list of electrical feeders. I want to cluster them by their topological characteristics: voltage level, total length, % of underground cable, state of the neutral. I first made a manual ...
4 votes
1 answer
2k views

K-Medoids swapping inside clusters

I'm a bit confused with concept of K-medoids. It seems that original algorithm (PAM) describes that swap step should be performed by swaping only one of the medoids with one non-medoid point from ...
5 votes
1 answer
2k views

Partitioning Around Medoids

I have a question regarding Partitioning Around Medoids (PAM) clustering algorithm, because everywhere I look, it is described differently. In every step of the algorithms do I swap only one medoid or ...
1 vote
1 answer
1k views

Compare clustering results based on intra cluster similarity

I am working on a project for my university. A part of this project is to compare the influence of PCA on clustering. Therefore I have a football player dataset that contains a feature called "...
1 vote
0 answers
295 views

More consistent medoids from Lloyd's algorithm?

I wrote an implementation of Lloyd's algorithm in Python and was running some tests. My data set is 1D (specifically dealing ...
2 votes
2 answers
2k views

Finding cluster number based on distance & max element count

Given two constraints: The maximum distance d an element can lie from a cluster centroid (or medoid) The maximum number of elements n in one cluster Is it possible to find the minimum number of ...
0 votes
0 answers
17 views

Bisecting K-mediods [duplicate]

Is there an algorithm like Bisecting K-mediods and what would its advantages/weaknesses be? It seems to me that it could be used well in combination of Dynamic Time Warping for clustering time series....