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Questions tagged [clusters]

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24 views

what arguments should I pass to dbscan or optic in order to divid the data in a specific way

I have thousands of very similar data set that needs to be divided in diagonal way to two groups. for example: and I tried to play with the argument of dbscan and optic as eps and minPoints and even ...
2
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1answer
42 views

Is there a scientific method for grouping continuous numbers for this problem

I use python, and I have a list of numbers that contains 19 elements and I would like to divide this list into 6 groups or fewer. The list could have numbers between 0 and 1. and it mustn't be ...
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2answers
43 views

Record Linkage problem

I am building Matching Alogoritm using ML.Project is to match Internal customer data with external customer data.Features are names,address,city,state and zip. We create pairs between data sets and ...
0
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1answer
51 views

Clustering, Mixed Data Set with Ordinal and Nominal Scale Data

After reading a bit how categorical data can be considered in clustering, I came to the conclusion that most of the post do not make distinction between nominal scale data e.g. colour: red, green, ...
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1answer
23 views

A bit confused regarding clustering of users in a dataset

I have a dataset of book reviews: ...
2
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1answer
34 views

how to implement a hierarchical clustering technique using parallel execution in R

In R, currently to implement wards method for hierarchical clustering, I use the following code - results <- hclust(data, "ward.D2"). However as my data size has ...
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0answers
13 views

How can I cluster data by using multiple views of the data with a common column using OpenRefine?

I need to cluster my data, but there are multiple ways to view the data such that I can't really place it all into a single table. I have been working with Open Refine to cluster this data but I keep ...
3
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1answer
33 views

Cluster Analysis - Comparing Same Individuals Clustered Across Different Datasets with different features

I have an interesting problem, and I think my Google is failing me since I can't find the same problem anywhere. I have a set of individuals. I have 4 different datasets, with (some) to (all) of ...
0
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2answers
261 views

multivariate clustering, dimensionality reduction and data scalling for regression

I have a dataset with approximately 20000 observations consisting of 40 independent and 1 dependent variable. My initial objective is to develop a model that will predict the dependent variable. I ...
0
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2answers
40 views

How to tell if the “clusters” I see in my pair plots are statistically significant or occurring by random chance?

I have a data set with one row per subject. Some variables include laboratory parameters for blood chemistry, hematology, etc. I also have some flag variables: any = 1 if the subject experienced an ...
5
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1answer
272 views

F - measure derivation (harmonic mean of precision and recall)

We can define the F - measure as follows: $F_{\alpha}=\frac{1}{\alpha \frac{1}{P}+(1-\alpha)\frac{1}{R}} $ Now we might be interested in choosen a good $\alpha$. In the article The truth of the ...
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3answers
705 views

k-means: Only one-dimensional cluster predictions in two-dimensional space

For this dataset, it seems that the predictions of my k-means model only consider the horizontal axis, although the cluster centers seem reasonable. Is something wrong with this classification? ...
1
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1answer
325 views

R: Pam function under cluster package not accepting data set having more than 65536 entries

I am running pam function for kmedoid under cluster package in R. My dataset has 1 million entries. It's throwing error saying Have 1 million observation but not more than 65536 observation ...
0
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2answers
392 views

Clustering: How to cluster multiple CSV files that each represent a Steam user

I am currently about to do clustering analysis regarding Steam users activity. So I have a thousands of CSV’s, each representing a Steam user and his/her purchased games (with ID and genre). I am ...
-1
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1answer
378 views

How does the seed value work in Weka for clustering?

I have recently been learning about the various clustering methods, and I decided to apply Furthest Point clustering in Weka with varying seed values. The seed value dictates the initial choice of ...
5
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1answer
120 views

Architecture for Machine Learning resource management

The problem: We have several people that do a lot of ML work in our lab and have more people asking to use our equipment. We have several machines that have Ubuntu on them that people share. This ...
3
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1answer
210 views

Why K-harmonic means is less sensitive to random initialization than K-means?

As we know that K-Means is a powerful clustering, however it often stuck with local minimum problem because of bad initialization . One of the solution is K-Harmonic means that use Harmonic Average as ...
1
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2answers
117 views

Notion of cluster centers and cluster comparison in Density Based Algorithms

I have done some research on clustering algorithms since for my goal is to cluster noisy data and identify outliers or small clusters as anomalies. I consider my data noisy because of my main ...
3
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0answers
210 views

How to setup a home-laptop cluster to 'practice' elasticsearch, hadoop, mesos and spark [closed]

I'd like to have elasticsearch, hadoop, mesos and spark on my home laptop (it's an 8GB with an intel i7 CPU) for practicing the setup of such frameworks and eventually to test their functions. I'm ...
2
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1answer
1k views

HDBSCAN cluster: still unclear to me how to chose 'min_cluster_size`

Hdbscan is an excellent technique to find the "optimal" number of clusters within your data when you have little a priori idea how many clusters should exist. This makes the method great for ...
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0answers
54 views

Spark Deeplearning4j Training Problem

I am training a model in Spark using Dl4J library in Yarn-Cluster mode. When I train the model on 2 lakh data (approx 200MB) then the job succeeds but when I go to train the model with 3 lakh data (...
0
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1answer
86 views

What is stored in heap structure in the following example?

I am planning to use heap structure to find the minimum distance between a set of 2D points and form a cluster.. and after to spend a couple of hours surfing on the internet, I have not still gotten a ...
2
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1answer
600 views

Spark 1.6.1 - Determining the number of clusters in a data set

There existis any way to find the number of cluster needed to use in K-Means? I'm having some difficulties to find a method to determine k... Many thanks!
0
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1answer
50 views

Built a Heap in Cluster algorithm

Does anyone could explain in details how heap structure works in Cluster Algorithm? I am planning to code CURE in Matlab (Clustering using representatives) but, at first, the paper mentions that all ...
3
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0answers
152 views

Clustering with Replicator Neural Network

I'm trying to cluster an unknown set of data with a replicator neural network. The number of clusters is determined by the number of neuron units in the middle layer, multiplied by the number of steps ...
3
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1answer
603 views

Derivation of Ward's formula for agglomerative clustering

Figure describe formula of ward method for hierarchical or agglomarative clustering i.e. increment of total error after merging two cluster. How did they get $$\frac{n_A\cdot n_B}{n_A+n_B} ||\vec ...
3
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3answers
1k views

Mahalanobis distance between two clusters

I want to calculate the Mahalanobis distance between cluster $a$ and cluster $b$, each consisting from a set of multidimensional points. Assuming no correlation, calculating the distance between a ...
1
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0answers
56 views

Creating Clusters in Excel office

I am trying to make group categories based on the similarity in attributes. For example; Car1: blue, big tires, slow, comfortable Car2: green, small tires, fast, comfortable Car3: blue, big tires, ...
6
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2answers
4k views

For which real world data sets does DBSCAN surpass K-means.?

For clustering, DBSCAN surpass k-means in terms of handling arbitrary shape data sets. In the most published papers about density based clustering, the experiments are performed with synthetic data ...
1
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1answer
267 views

How to set weight in Weighted Kernel K-Means?

The objective function of kernel K-means is $$ \sum\limits_{c=1}^k \sum\nolimits_{a_i \in c} w_i \Vert \phi(a_i)- m_c \Vert^2 \ $$ where $$ m_c = \frac{\sum\nolimits_{a_i \in c }w_i\phi(a_i)...
3
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1answer
12k views

How to plot/visualize clusters in scikit-learn (sklearn)?

I have done some clustering and I would like to visualize the results. Here is the function I have written to plot my clusters: ...
23
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4answers
19k views

Is it necessary to standardize your data before clustering?

Is it necessary to standardize your data before cluster? In the example from scikit learn about DBSCAN, here they do this in the line: ...
2
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0answers
62 views

Spatial clustering of data points on a grid to obtain variable resolution map with constant statistical confidence

I have a grey valued image which is calculated as the mean of a series of images. The value of each pixel is therefore associated to a standard error. The pixel values and the relative standard error ...
2
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1answer
89 views

Joint spatial clustering: How to force clusters to minimally contain datapoints from all datasets

I want to jointly cluster datapoints coming from different datasets (50 datasets with around 2000 points each). I would like to then extract information associated to the datapoints belonging to the ...
2
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1answer
164 views

What kind of analysis can I do in this dataset? [closed]

I have a dataset of clients (their city, name, age, gender, number of children) and another dataset about the products that they have bought. i have been asked to do: extract knowledge about client ...
12
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3answers
1k views

Instances vs. cores when using EC2

Working on what could often be called "medium data" projects, I've been able to parallelize my code (mostly for modeling and prediction in Python) on a single system across anywhere from 4 to 32 cores....