k-means is a family of cluster analysis methods in which you specify the number of clusters you expect. This is as opposed to hierarchical cluster analysis methods.

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Outlier detection using k-means in a binary classification problem

I'm using k-means in every class of a binary classification problem and remove samples that have high distance from center of my features (21 features so 21 ...
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62 views

Using k-means with other metrics

So I realize this has been asked before: e.g. What are the use cases related to cluster analysis of different distance metrics? but I've found the answers somewhat contradictory to what is suggested ...
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What's a good way to mentally visualize n dimensions in a k means

I've been using k-means to do some clustering and one of the ideas I'm struggling with is the n dimensions aspect. If I were clustering housing prices vs sq. feet its just a simple 2d graph. That I ...
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How do I create clusters with a completely categorical data?

I am working on the project that requires data mining. I have been asked to use R. I have a dataset with all categorical variables and would like to form clusters on that. I am unable to figure out ...
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28 views

Correlated variables in kmeans clustering

I have a dataset with 3 variables: A, B and C. Now, A and B are ordinal variables (i.e.; the result of two questions measured using a 5-point Likert), whereas B is continuous. A and B are also ...
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19 views

How to measure the similarity of k-means clustering using different datasets?

I run k-means clustering on my dataset (100 samples in total) and partition the data into k=5 clusters. Then I want to test how robust of the k-means can be; however, I haven't got more new data ...
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21 views

How can I evaluate the accuracy of a clustering when I don't have information on the true class labels?

Already classified data set for the t-shirt factory problem I want to calculate the accuracy of my algorithm. I have the training data without any size information and I couldn't find the classified ...
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41 views

Apache Spark - MLlib - K-Means

I want to perform a K-Means task and fail training the model and get kicked out of Sparks scala shell before I get my result metrics. I am not sure if the input format is the problem or something ...
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R skmeans package - where does this error come from: “missing value where TRUE/FALSE needed” [migrated]

I tried to cluster my data in accordance with the manual provided by the skmeans packages's manual page I started by installing all required packages. I then imported my data table, and made a matrix ...
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9 views

Calculating the Similarity of Survey Responses

I was wondering if anyone had experimented with different functions for calculating the similarity of two sets of survey responses. I am going to be plugging it into a hierarchical clustering algo and ...
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25 views

Spherical K-means Clustering in R

I have a large data set that I would like to cluster using spherical K means algorithm. However, I am relatively new to this subject and R in general. Most of my knowledge is self taught and I am ...
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39 views

I find very different results using a k-means or two-step clustering method. How is this?

I want to use a cluster analysis (CA) in SPSS to define different profiles in my dataset. I am using different continuous variables for this, including several neuropsychiatric measures. I am new in ...
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17 views

Spectral clustering using Technics other than kmeans

In spectral clustering, the algorithm suggests performing K-means to k eigenvectors of the resulted Laplacian matrix. My question is: 'Can I use other clustering algorithms such as K-medoids or other ...
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49 views

k-means vs k-median?

I know there is k-means clustering algorithm and k-median. One that uses the mean as the center of the cluster and the other uses the median. My question is: when/where to use which?
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132 views

K-means cluster analysis with K=2 as a binary classifier

I used two variables, height and weight, and using K-means cluster analysis with $K=2$, two clusters were obtained. I used $K=2$, as the observations either belong to men or women. I then compared the ...
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44 views

k-means clustering on percentages

Can we do k-means clustering on percentage data (like 56%, 44%, 22%, 13%, etc.)? There is a data set, and data in various parts are measured in percentages.
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31 views

k-means in R generates same number of clusters but different cluster label

Hi there I am running a k-means code in R with the same data and with the same number of clusters, in this case 3, but each time that I run the code, the cluster label changes, for example. In the ...
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34 views

A clustering and classification question

I'm trying to classify my set of data into two classes (introvert / extrovert). I was thinking of using a decision tree at first, but I don't have any potential known results in order to create my ...
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30 views

Classifying a set of photos to places

I want to cluster photos and map them to places. As input I have Photos with locations (lat, long) Places - some as (imprecise) bounding boxes, some just as points, maybe others as bounding ...
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48 views

clustering accuracy

I have a general doubt regarding clustering. I have a data set of size 1196*18675. where 1196 is the no of documents. I am trying to cluster the data with k=7 using k-means. Each time the clustered ...
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36 views

K-means metrics

I have read through the scikit learn documentation and Googled to no avail. I have 2000 data sets, clustered as the picture shows. Some of the clusters, as shown, are wrong, here the red cluster. I ...
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10 views

Turning MiniBatchKMeans into Fuzzy MiniBatchKMeans

I'm using Scikit-Learn, which has an implementation of MiniBatchKMeans. I'm very inexperienced with ML, so I'm wondering how (if ...
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39 views

Which clustering technique to use for a temporal dataset?

I have seen a similar question but thought I'd ask my own to hopefully garner some usefull feedback. Basically, I have a large temporal dataset, consisting of domestic smart energy meter use ...
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29 views

Avoid local minima in kmeans

Many machine learning techniques suffer from the curse of local minima, one of them is K-means. I am using a matlab script for a computer vision task. One of the first steps I do is kmeans clustering ...
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29 views

K-means Stuck in 1 cluster

I'm working on a problem using the encog Kmeans library and NO MATTER what features I add to the model, it always gets stuck in one of the clusters. ALL of the samples are lumped into one cluster ...
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68 views

Inputs to k-means are often normalized per-feature. Why not fully whiten the data instead?

We often normalize inputs to the k-means algorithm by 1) subtracting the mean on a per-feature basis and 2) dividing by the standard deviation on a per-feature basis. Some rational behind this is ...
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33 views

Assigning meaningful cluster name automatically

The objective of my work is to cluster the text documents. Once the documents are clustered, traditionally the system will assign numeric value for the clustered group. For example if I have 5 ...
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48 views

K-means cluster Analysis and 4-point Likert Scales

Is there a concern using a 4-point likert-type scale (i.e., agreement) when attempting a cluster analysis using k-means clustering? Most of the data for the items in my data set are favorable (e.g., ...
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81 views

Feature / attribute selection for k-means or other clustering

It seems to me that in literature it is assumed that one knows which features / attributes to choose to characterize an item in clustering. If I have a database with items which have many attributes, ...
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35 views

Edge Probabilty Using KL-Divergence Code in Python

Its a little complicated question, so please bear with me. I am doing Image Segmentation using Swendsen-Wang method for Image Analysis./ (stat.fsu.edu/~abarbu/papers/jcgs.pdf) I have to calculate ...
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81 views

Clustering algorithms for extremely sparse data

I am trying to cluster an extremely sparse text corpus, and I know the number of clusters (my data is the title and author list of scientific publications, for which I already know the number of ...
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57 views

Clustering on a data set with mixed variables

I have a data set consisting of $n$ elements with $d$ features for each element ($x_{i,f}$ means the value for the f-th feature of the i-th element). I would like to cluster this data set into $k$ ...
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10 views

Comparing to vectors of labels that contain different labels, but the same number, and the same places

Problem: After doing two cluster analysis, I get two arrays $V_1$ and $V_2$ of length $N$. I have a groundtruth vector as well $GT$. I want to make the comparison, which is label invariant. Say first ...
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ML Bank transactions assignement to invoices

In a effort to reduce human intervention, I'm trying to optimize the process of assigning bank transactions to invoices. This task should be done once every year, so we can assume our dataset won't ...
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374 views

Clusterings that can be caused by K-means

I have gotten the following question as a test question for my exam and I simply cannot understand the answer. A scatter plot of the data projected onto the first two principal components is shown ...
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K-means clustering and R - what to do next?

I used kmeans command on my data-frame (as suggested in "R and Data Mining: Examples and Case studies"). Now my data is clustered into x number of cluster. What ...
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36 views

How to test the significance of clusters?

How can one test the significance of the clusters obtained after a clustering procedure? Are there separate tests for the distance/similarity/dissimilarity measure used to get the distance matrix and ...
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49 views

Intuition behind the Calinski-Harabasz Index

Given $CH(k) = [B(k) / W(k) ] \times [(n-k)/(k-1)]$, where $n$ = # data points $k$ = # clusters $W(k)$ = within cluster variation $B(k)$ = between cluster variation. It is my understanding that the ...
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66 views

Interpretation of NbClust result

The plots show the output of NbClust(). By looking at the plot, is that correct to say that k=5 is the optimal number of ...
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24 views

Square distance and likelihood in k-means

In k-means algorithm, the distance minimization step is equivalent to maximize likelihood: $P(X|\theta)$ or to maximize posterior distribution $P(\theta|X)$? I think it's more logical to maximize ...
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12 views

K-means finds less than K groups [duplicate]

According to the $K$-means algorithm, Randomly assign a group or cluster to each point. # initial step Compute the centroids of all the $K$ groups. Reassign each point to the closest groups by ...
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121 views

Bayesian Networks and discretization of variables using K-means clustering

In many approaches to learning Bayesian Networks a solution to tackle continuous variables is to discretize them and apply one of the well established techniques for learning Bayesian Networks ...
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18 views

Clustering groups that have replicated measures: hierarchical clustering on group-average VS regression tree

I measured 2 continous dependent variables (V1 and V2) on 10 occasions (10 replicates) for each of 4 groups. I aim to cluster my groups. i.e. I dont want to cluster replicates, since this could mix ...
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48 views

Is there an efficient way to discriminate space based on K-Means results?

Suppose we done K-Means and got K centroids of clusters and we want to tag new points based on those K centroids. UPDATE: These K centroids are given to me, so I can't go for another clustering ...
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200 views

usefulness of k-means clustering on high dimensional data [duplicate]

I wonder what is the usefulness of k-means clustering in high dimensional spaces, and why it can be better (or not) than other clustering methods when dealing with high dimensional spaces.
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111 views

Streaming k-means

I want to perform something like streaming/online/out-of-core kmeans clustering on large data. Here is simple idea: Break all data into N chunks. Read from disk 1st chunk and calculate centroids ...
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58 views

Alternative to spherical K-Means for clustering large high dimensional dataset

What are some alternatives to Spherical K-Means for clustering very large datasets of high dimension? I'm looking for something that will be fast even on large datasets, and preferably will not ...
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Clustering Techniques

I'm a little new to data mining and would definitely appreciate some tips. I'm using clustering algorithms looking for possible grouping in some variables described below. I've been using the Excel ...
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115 views

k-means + linear regression: How to split the data for validation

I want to cluster my data first using k-means and then determine a regression model for each cluster. Then I want to evaluate the performance of this approach using split validation. I can think of ...
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40 views

Standardizing variables for k-means?

I only have two variables and they are on the same scale. However, the variance corresponding to the first variable is approximately 0.609, whereas for the second variable is 0.154. So my question is ...