Questions tagged [similarities]

Measures of closeness between distributions, clusterings, data sets or other objects.

Filter by
Sorted by
Tagged with
0
votes
0answers
20 views

Techniques to measure similarities between instances and a dataset

I'd like to get a similarity measure between my dataset and a set of instances. For example, let's say I have a dataset with 4 features and n rows - ...
0
votes
0answers
16 views

which algorithm is preferred for knowledge based recommendation system? [closed]

I would like to know the recommendation algorithm commonly used for knowledge based recommendation.
1
vote
1answer
27 views

How to check if two matrices contain similar information?

I have two rectangular (big) matrices A and B, of shape N×M. Each element, in both matrices, represents a “similarity” between two entities, n and m, which are vectors. In case it matters, in the ...
0
votes
0answers
8 views

NLP keywords to realize approximate string and meaning matching

What I would like to do I would like to try to unite words into groups for approximate string and meaning matching. However, there are several types to match words. I'm not sure about its ...
0
votes
0answers
13 views

Best way to compare time series data similiarity

I have two time series'. One represents ground truth heart rate in a a subject (top in blue), and the other a prediction of heart rate using a novel method (bottom in orange). It looks like this: ...
0
votes
0answers
14 views

Specialized Clustering algorithm for Similarity Matrix

I have a (bit of a unique?) clustering problem. Here are the important details: The data entities themselves don't have feature representations, but there are custom similarity scores [0-1] computed ...
2
votes
1answer
53 views

Computing similarity between a series of two datasets' Principal Components

I have implemented a framework where two data matrices (with same rows or data points, but different columns or features) are compared by the Pearson correlation of their first principal components (...
0
votes
1answer
43 views

Intended interpretation of one-mode, three-way (dis)similarities?

I have what I think is a very simple question, the answer has just eluded me so far. A two-way similarity, $s_{ij}$ (for objects $i$ and $j$) can be interpreted fairly straightforwardly as the degree ...
2
votes
0answers
25 views

How “clusterable” is an affinity matrix?

In my problem I have some affinity matrices computed from different similarity functions. I'd like to know if there is a measure that assesses how "clusterable" these matrices are. In other ...
0
votes
0answers
11 views

Best way to suggest 'n' number of users based on demographic, interests data

I have to build a recommendation engine which suggests 'n' number of similar users to a user. I tried to implement this in user-user recommendation system methodology and unsupervised learning. Theres ...
0
votes
0answers
19 views

How best to compare an individual profile with the average profile?

I asked people to describe their ten most important life decisions. For each decision, I recorded the age at which the decision occurred and its category. There were 57 total categories (e.g., ...
0
votes
0answers
15 views

Comparing Directed Unweighted Graphs with a Dissimilar Number of Nodes

I'm looking to compare 2 unweighted directed graphs and get an (ideally differentiable) similarity score. Both graphs describe a trajectory in a 2d space. The reference graph is a step by step guide ...
0
votes
1answer
11 views

String distance equations for fuzzy-matching person names

A reproducible example with a small bit of R code is available in this stackoverflow post (link so I dont need to re-type out the code). The fuzzytext library in R ...
0
votes
0answers
15 views

Similarity matrix for directed graph vs. undirected graph producing odd/disparate numbers on diagonal (i.e. self-similarity)

In a correlation, distance, or similarity matrix, comparisons to self should be along the diagonal as a constant 1 or 0. However, I have found that while similarity to self is a constant 0 in ...
2
votes
0answers
14 views

Normalized measures for curve slope similarity

The website "Spurious Correlations" lists many curves that have a similar shape and gives their correlation coefficient. Whilst the Pearson correlation $r$ measures whether deviations from ...
1
vote
0answers
27 views

Why are we interested in gradient with respect to input?

I am learning about sampling methods for Deep Embedding Learning. I was reading an article named: "Sampling Matters in Deep Embedding Learning" (https://arxiv.org/abs/1706.07567). In the ...
9
votes
1answer
149 views

What's an intuitive way to understand how KL divergence differs from other similarity metrics?

The general intuition I have seen for KL divergence is that it computes the difference in expected length sampling from distribution $P$ with an optimal code for $P$ versus sampling from distribution $...
1
vote
1answer
20 views

Maximally dissimilar subset

Given a N-dimensional similarity matrix, is there an efficient way of finding the subset of size M<N that is maximally dissimilar? (I guess that the notion of maximally dissimilar is not completely ...
0
votes
1answer
14 views

Metrics in comparing the rank orders of elements from 2 vectors

I am working on sampling a posterior distribution for parameters in my model using approximate Bayesian computation (ABC). I would like to come up with a summary statistic to compare the similarity/...
0
votes
0answers
29 views

Similarity between two nominal datasets?

I am trying to compare (estimate similarity) two nominal datasets which are representing the same output. For example, my first data output is (1)Low (2)Low (3) Medium (4) High etc. Second data output ...
1
vote
0answers
18 views

Find time series that best approximates another time series, question about detrending

The task is to figure out which variable best "approximates" the behavior of the target variable over time, so that it could be potentially used as a substitute later on (e.g. because it's ...
1
vote
1answer
23 views

what type of recommender system do I need? [closed]

I'm trying to make a recommendation for my customer based on item feature and priority of item. For example, if there is a customer who wants to buy item A from category X, I want to find items with ...
0
votes
0answers
30 views

How to calculate the similarity of data with noise?

I'm stuck on calculating similarity. Please tell me in which direction to move. There are three files of different lengths that need to be compared for similarity. It is supposed to use the cosine ...
0
votes
0answers
21 views

Similarity metric for one-dimensional time-series data-sets

I have a setup consisting of measured (one-dimensional) sensor data from n subjects. For each subject, measurements were performed from different angles. The amounts of angles and acquired ...
1
vote
1answer
24 views

Alignment algorithm

I am looking for an algorithm that can align a vector of numbers . I don't know exactly where to look because I am not sure how you would name it, so I am sorry if this is already asked (I couldn't ...
0
votes
0answers
24 views

How to compare two high dimensional data samples

I have an anomlay detection problem in high dimensional data. I am using an isolation forest to detect anomalies in this data in an unsupervised manner. I have come across two samples in my data ...
0
votes
1answer
46 views

How to find similarity in R or Python? [closed]

I have a data set as I've shown below: It shows which book is sold by which shop. Also, every book_id has a type. ...
0
votes
0answers
10 views

What's the difference between the maximum dissimilarity within a cluster and the cluster's diameter?

I'm wondering what the difference is between the maximum dissimilarity within a cluster and the cluster's diameter? Thanks!
0
votes
0answers
30 views

Compare differences between 2 datasets with Jensen-Shannon divergence

I have two medical imaging datasets: Brain MRI from institution A Brain MRI from institution B Because of different acquisition parameters the intensity distribution in those datasets could be ...
0
votes
0answers
16 views

How to find the similarity?

I have a problem statement but I am not sure how to approach it accurately. Let me explain the statement. Assume that I have a website that many shops are selling books. Some books are very demanded,...
2
votes
0answers
38 views

How to measure similarity between tag distributions?

I have a table of movie tag assignments where each row is (userId, tagId, movieId). I'm using test data set from Movielens with a million rows. I want a function that given two films returns a ...
0
votes
0answers
17 views

Similarity index between 2 unevenly sampled time series

Say I have 2 time series $s_1$ and $s_2$ with independent variable $x_1$, and dependent value $y$. These 2 series are not evenly sampled across $x_1$, or even sampled at the same rate. Now, I have ...
1
vote
0answers
33 views

Statistically, how to find a subset of values which seems to have same magnitude?

Data Set Description I have a data set where students' spent time on study is available. In this table, student 4 to student 10 seem to spend similar amount of time on study. There is very little ...
1
vote
0answers
22 views

Anconva or Anova for multifactor analysis

I have non-normal plankton community data, where rows are sites and columns are species (dependent) and a few factors. I want to check the influence of season on community (dis)similarities but am ...
0
votes
0answers
6 views

Is there a way to determine the most similar variables from a number of different time-series?

I have a time-series data frame with 27 different variables. In reality, they are all different instruments recording the same measurand every 5 minutes. I want to know if there is a way of ...
1
vote
0answers
24 views

Check which parameter causes less dispersion in a sample set - When to use CV (Coefficient of Variation) or CD (Coefficient of Dispersion) etc

The overall goal is to extract/engineer features from approximately 100 segments (various lengths but always more than 80 data points) that are as similar as possible to each other and have a very low ...
2
votes
0answers
19 views

Similarity between clusters/groups?

I have a dataset consisting of multiple groups in a high dimensional space. An example is shown below: What would be the best way to calculate similarities between groups. Say how similar is group A ...
1
vote
1answer
23 views

Similar histograms after removing mean and dividing with std

I have four time-series, of a physical quantity (heat flux). When I remove the mean value from my data points Xn = X - mean(X) and divide them with the standard deviation Xn' = Xn/std(Xn) the ...
0
votes
1answer
61 views

Using similarity matrix as a correlation input

I am using an approach to decompose sigmoidal signals in R. Briefly, signals are decomposed into a subset of components and then a custom value of similarity is computed among samples defined by 2 ...
0
votes
0answers
58 views

How to avoid non-independence of data points when measuring alignment?

I am trying to compare groups on alignment. A group has high alignment to the extent that members of the group are similar to one another. A group has low alignment to the extent that members of the ...
0
votes
0answers
15 views

How to group products with similar attributes?

Customers ask me for a quote for a a product. I might have quoted a nearly identical product for a different customer already albeit with slightly different attributes. Only in rare cases they're ...
1
vote
0answers
79 views

how does VAT algorithm works

I want to know how the VAT algorithm for cluster tendency works in detail. As you can see in the picture below R is the dissimilarity matrix and R-tilda is the ordered dissimilarity matrix. What is ...
1
vote
0answers
29 views

Kullback-Leibler Divergence vs Normalized Cross Correlation

I have couple of time series data that I want to cluster. As I was looking for ways to calculate similarity for time series data, I came across couple of different similarity methods. What I am ...
0
votes
0answers
18 views

Compare similarity between two different clusters having few similar fields?

I have two datasets, one is mentor dataset another is jobseeker dataset. My ultimate goal is to recommend a jobseeker to mentor based on skills and location (skills jobseeker has but need mentorship ...
0
votes
0answers
38 views

Does DTW return smaller distance measure than Euclidean Distance?

QUESTION 1: When computing the distance between two time series, shouldn't the DTW distance measure return a smaller distance than the Euclidean distance (assuming DTW internally uses the Euclidean ...
0
votes
0answers
56 views

Finding weights to be used by an Euclidean distance function for vectors with weighted components in a multi-dimensional space, using only sample data

I have a multi-dimensional space with $d$ dimensions wherein $i$ vectors ($v_1 ... v_i$) with $d$ components live. I want to find a function $s(v_a, v_b)$ which takes in two of these vectors and ...
1
vote
0answers
14 views

the OKCupid formula (and other ways of estimating similarity with limited data)

Say I have a test, that receives a string and returns either Belongs or Does Not Belong (to a set) I know the true answers (if each sample belongs to the set or not), and I want to evaluate the ...
0
votes
0answers
10 views

Finding the relative 'importance' of different vector components when defining distance of two vectors in a space [duplicate]

I have a multi-dimensional space with $d$ dimensions wherein $i$ vectors ($v_1 ... v_i$) with $d$ components live. I want to find a function $s(v_a, v_b)$ which takes in two of these vectors and ...
0
votes
0answers
33 views

Is there a way calculate a gradient of dissimilarity across multiple sites using presence/absence data?

I’ve been trying to come up with a metric for species (dis)similarity for fish in a series based on presence or absence data that gives a value of 1 or 0 for each lake. From my research, it seems like ...
0
votes
0answers
11 views

Finding distance/similarity function between two vectors in a multi-dimensional space, with weighted components/dimensions [duplicate]

I have a multi-dimensional space with $d$ dimensions wherein $i$ vectors ($v_1 ... v_i$) with $d$ components live. I want to find a function $s(v_a, v_b)$ which takes in two of these vectors and ...

1
2 3 4 5
9