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0
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2answers
92 views

Excel: which products are most frequently ordered together? (clustering question)

I'd like to recruit your help in coming up with an Excel-based method to analyse a set of raw ordering data where each item is on its own row. So, in the data below, order 111 contains two part ...
0
votes
0answers
37 views

What is this problem called in machine learning research?

Given 2 sets of entities from 2 different classes described by properties $f_1...f_n$, any 2 entities from the 2 different classes together have a score: ${\rm Score}(c_1e_1,c_2e_1) = y$. How ...
1
vote
0answers
25 views

How to estimate similarity between several probability distributions?

I have several set of probability distributions. I want to reliably estimate consistency across distributions inside each set. Literature contains methods to compare two distributions: ...
0
votes
1answer
13 views

Similarity between two samples of spacialized data ignoring local fluctuations

I have data from a set of sensors, and would like to measure similarity between two samples of data ignoring local fluctuations. My problem is, my sensors are not regularly placed : some are quite ...
0
votes
0answers
28 views

Dissimilar to multiple points

I have a few points in multiple dimensions. I am able to compute similarity between those items (using, say Cosine distance). For example, ...
1
vote
1answer
28 views

Similarity between different length vectors containing related items

I have a vector (V1) with which I need to calculate the similarity of other vectors (ex V2,V3 ... ) which may be of different lengths. The different angle here is that the elements inside the vectors ...
0
votes
2answers
28 views

Similarity of time series

I have several time series based on moving average values from a single data set (x-axis=date, y=moving average count of car type), i.e. the moving average values are calculated from the same raw ...
0
votes
0answers
67 views

Clustering communication patterns to detect multiple identities

I have a data set of communication patterns between chatting agents. Each agent can have multiple profiles or identities. I am interested in developing a way to investigate the similarity between ...
0
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0answers
25 views

Calculate similarity of waiting times of users

Let's say I have waiting times(seconds) of users in web pages. ...
1
vote
1answer
19 views

calculate Levenshtein Distance for web click stream data

I want to calculate Levenshtein Distance between to web click paths. I have a web page list around 500. ...
0
votes
0answers
21 views

What is the best test to compare pattern similarity in different condition?

I have several subjects, for each subject I have two measure (pre and post treatment) of several parameters, I have calculated a multivariate similarity measure (Mahalanobis distance) between each ...
3
votes
0answers
33 views

Using similarity matrix to measure diversity of a group

I wish to measure the "diversity" of a group of objects. Right now I'm using Euclidean distance to compute the similarity matrix between all the objects in the group. I'm searching for a measure of ...
2
votes
2answers
105 views

Building the connection between cosine similarity and correlation in R

According to some articles (e.g. here) correlation is just a centered version of cosine similarity. I use the following code to calculate the cosine similarity matrix of the column vectors of a matrix ...
4
votes
1answer
109 views

Finding similarity between the objects ( Actually how to justify the similarity of objects in mathematics form )

I have developed a system to trace the outlines of (images of) objects. Now I want to test whether two independent traces represent a common feature. Imagine two people (or machines) tracing the ...
0
votes
0answers
16 views

Similarity in a vector space model with skewed feature distribution

I want to compute the pairwise cosine similarity of items in a vector space of a very high dimensionality . My input matrix is very sparse, but the number of nonzero elements per item follows a very ...
1
vote
1answer
26 views

Similarity Coefficient and Geochemical Correlation

I have a set of around 160 samples from different sediment bodies, or stratigraphic units, which I am attempting to correlate using geochemical analysis of 25 elements for each sample, and a ...
2
votes
0answers
37 views

What is a good technique for grouping objects based on binary or dichotomous traits?

I have a set of objects each of which has a list of traits. Data on the traits is binary: an object has a trait or does not. The number of objects that I have is moderately greater than the number ...
0
votes
0answers
29 views

Converting a similarity to a dissimilarity [duplicate]

I am working on a clustering problem for which I have to manually choose the number of clusters. I have a visualization tool that helps me decide whether the clusters are good. In order to ...
4
votes
0answers
119 views

Compute Shannon entropy between every row of a large, sparse matrix

I have a sparse, binary matrix of user (rows) and items (columns). Each element of this matrix is either 0 or 1: ...
1
vote
0answers
52 views

Cosine similarity for a group of vectors

I am starting to work in R with the following case: 35 countries have scores between [0,1] in 120 dimensions and I need to show that there are differences in the way their scores distribute across ...
0
votes
2answers
107 views

Similarity measure between two variables

I want to find the similarity factor (some numerical value) between two variables. Example: row 1: 5.1, 3.5, 1.4, 0.2 rows 2: 4.9, 3.1, 1.5, 0.1 How to find similarity factor between these two ...
1
vote
1answer
65 views

Determining similar users from hierarchical clustering

I use hierarchical clustering to cluster users which are similar to each other based on a Jaccard coefficient. I have now coded a solution to extract similar users based on hierarchical clustering: ...
2
votes
0answers
29 views

How to calculate the similarity of two corpora (each of which contains a set of documents)?

I have two corpora for example, each of which contains a set of different documents, and each document are already represented as a vector of words in a certain way. The two corpora are small, only ...
0
votes
0answers
42 views

Learning from distance matrices

I have a task to build multi-task classification model based on distance (similarity) matrix only. They are already precalculated and no changes here can be applied. Can you, please, recommend me ...
0
votes
0answers
34 views

Dataset similarity measurement

Suppose: For each input data, I could obtain true result as well as experiment result from my algorithm, one example is The true result is A = {a, b, c}, ...
0
votes
2answers
52 views

Similarity measure between multiple distributions

To compare distributions, it is common to use box blots. I'm looking for a similarity measure that calculates whether distributions are the similar or not. Ideally, given that e.g. four ...
1
vote
1answer
96 views

Clarification needed about min/sim hashing + LSH

I have a reasonable understanding of the technique to detect similar documents consisting in first computing their minhash signatures (from their shingles, or n-grams), and then use an LSH-based ...
2
votes
0answers
318 views

How to get Bhattacharyya Distance in Excel (or Matlab, or R)

I have several histograms which I would like to compare to one reference histogram to see which one is the most similar to the reference in terms of the shape of the distribution. Kologorov-Smirnov ...
0
votes
2answers
140 views

How similar are my 2 data sets?

I am kind of stuck with an easy question: I have two data sets with experimental data. The data sets do not have the same size. I would like to show that these data sets are possibly coming from the ...
0
votes
0answers
23 views

How a problem of calculating a probability of two differently represented objects being the same is called?

I'm solving a task of matching (i.e., asserting that different "accounts" represent the same object) social network's profiles of users with their representation in a database of firms founders. The ...
4
votes
4answers
224 views

How do I deal with large data similarity computation?

I have lot of records like this: M is about 10 million and N is about 100K. Now I want to apply collaborative filtering on ...
1
vote
1answer
121 views

similarity measures with missing values

How to handle missing values when computing similarity (or distances)? (I have binary feature values and do use the simple matching coefficient, but I feel that the answer to this question may be more ...
0
votes
0answers
20 views

Comparing two items with various parameters of different units

Not a big stats guy, but I dabble in programming and frequent stackoverflow and figured this would be a good place to turn. Here's what I'm looking for. I have a set of food items. Each has a number ...
3
votes
0answers
63 views

Kernel interpretation of Manhattan distance / Lp norms

Euclidean distance corresponds to the linear kernel similarity via: $$d_\text{Euclidean}(x,y)^2=\sum_i (x_i-y_i)^2=\sum_i x_i^2 + y_i^2 - 2 x_i y_i = ...
0
votes
2answers
50 views

Negative values distance model between 2 sets

I have two sets, $A$ and $B$, containing string values. I am trying to model the relationship between sets $A$ and $B$ by computing the following distance: $d = \frac{ \mid A \mid + \mid B \mid- \mid ...
2
votes
0answers
110 views

Comparing facial curvature of two human faces

I need help determining if what I'm doing is sufficient. I have extracted the "curvature" from two human faces (essentially the curve that goes from one ear, down the face to the chin, and back up to ...
0
votes
1answer
125 views

coding survey data for cosine similarity and euclidean distance?

I want to know how to code survey data such that a similarity function can be applied on it. Say I want to use cosine similarity. All the search results and QA I've found while in my search deal only ...
1
vote
0answers
30 views

Finding similarities using Wavelet transform

I have a time serie and I want to find similarities in it. For the first step I have calculated Haar-wavelet coefficients for this time serie, and now I don't know exactly how should I continue ...
2
votes
1answer
82 views

Combining similarity scores

I have a list of m x n similarity score matrix, something like ...
0
votes
0answers
60 views

How to analyse environmental temperature datasets

I need some advice regarding my statistical analyses with SPSS. I have a dataset of temperatures recorded automatically every 30 minutes in three different habitat types for the same time frame. I ...
0
votes
0answers
15 views

Most similar combination of partitions to the rest of group

I have a number of sample sequences of data that I want to compare with another large number of sequences of data. These samples are partitioned in between and I want to see which combination of ...
0
votes
0answers
59 views

Chi-Square Difference in Similarity Matrix

I am attempting to implement an algorithm and to construct a similarity matrix looking at the pairwise similarity between N distributions. The instructions are that each element in the similarity ...
0
votes
0answers
112 views

Computing Jensen-Shannon Divergence between discrete and continuous distribution

Is it possible to compute the Jensen-Shannon divergence between a discrete and a continuous probability distribution, e.g. between a standard normal distribution and a distribution taking the values ...
0
votes
1answer
80 views

What methods exist to measure how similar a set of sampled distributions are to each other?

I have a set of distributions that are sampled. How do I measure their similarity between themselves or as a group/set? So, given a finite domain for a sampled function$F_j(x)$, with $x_i \in ...
-1
votes
1answer
87 views

Cluster centroids visualization

I've some data that I've clustered and calculate the similitude within my cluster centroids to spot which class centroids are close to which ones. My goal was to visualize this as a map of points. I ...
0
votes
0answers
71 views

How to explain LSA results

I used an LSA (Latent Semantic Analysis) code in python to find the similarity of two documents. The results of the code are the following, but I cannot understand what is the score of the similarity. ...
1
vote
0answers
53 views

Appropriate distance measures

I am working with hyperspectral image data in R, so I have subset an image to a region of 5000 pixels, each containing a vector 254 bands in length. I would like to cluster this data in order to try ...
1
vote
1answer
303 views

recommenderlab, why does the similarity function return only 0's and 1's? [closed]

In a matrix with user ratings I want to calculate similarities between the first ten users and the rest of the users. I use the method "jaccard" for the similarity calculation in recommenderlab. My ...
2
votes
1answer
354 views

Kullback-Leibler divergence of two normal distributions

I was recently trying to find a way to compute the KL-divergence between 2 populations that are normally distributed using the mean and variance of each population. But I found several different ...
0
votes
0answers
202 views

Clustering text with python

I asked on stackoverflow but they suggest me to move here for better answers. I copy paste the question. I decide to play a little with similarities and clustering text. I have already create the ...