The tag has no usage guidance.

learn more… | top users | synonyms

1
vote
0answers
11 views

R clustering using mclust: BIC are often NA

I'm working on segmentation/clustering and trying to use Gaussian Mixture Modelling for Model-Based Clustering. I'm using the R package Mclust in order to come up with the best fit for my data. All ...
1
vote
1answer
14 views

Determine the n largest intervals of noise in an audio file

I have audio files that contain interviews with long periods of silence. n - Number of interviews for a given audio file. I need to split the audio into periods where the interviews are actually ...
3
votes
0answers
31 views

Help in understanding a clustering technique using neural network

I am having difficulty in understanding a technique for clustering and segmentation of biomedical images using the concept of time series. The paper on which the Question is based is : M. Lacomi et. ...
0
votes
1answer
22 views

Segmentation of Geodemographic Data

I have a dataset that has 5 variables (columns). These are median house price, median income, number of people with no educational degree, number of people with high school degree, number of people ...
1
vote
0answers
8 views

Segmentation - Making Segments Sharper

I have a question. We’ve done a study that looks at the youth’s attitudes towards “social issues” such as water, sanitation and public health. We then segmented the population using factor analysis ...
0
votes
0answers
12 views

How to check if Gaussian Mixture Model is appropriate for clustering

I have a dataset consisting of 19 variables and ~5400 observations. I've run GMM on it to obtain some clusters. When I analyze these clusters, I come across random (seemingly) observations which ...
0
votes
1answer
107 views

User segmentation by clustering with sparse data

Imagine that I have 100k users and 1k categories. For each user, up to 5 categories, I know how much money they have spent. Obviously my data is very sparse. Now I want to group users by the money ...
0
votes
0answers
20 views

How to classify data using classification weights and coefficients

I have run a segmentation and discriminant analysis on some data. I used a software that does all of this and outputs the classification weights and coefficients for classifying out of sample data. ...
1
vote
1answer
37 views

Segmentation analysis based on Likert [closed]

I would like to do a segmentation analysis based on a Likert scale survey. I want to ask respondents to rate certain attributes on a scale of 5 points (not valuable at all, not very valuable, neutral, ...
1
vote
0answers
207 views

k means for segmenting time series

I understand the fundamentals of k means clustering (though never applied it myself). Now, I am trying to understand how to segment a multivariate time series using k means. I understand that the ...
0
votes
0answers
23 views

Determining dates of regime switches in historical time series

I am interested in determining the dates of regime switches (i.e. starting points of segments of a (univariate) time series that show similar behaviour, such as similar volatility) in a historical ...
1
vote
0answers
25 views

What are good / simple techniques available for segmenting non-cursive handwriting images?

I need to process English hand-written form fields. So the hand-writings are expected to be mostly non-cursive but the letters may occasionally overlap with each other slightly, with some punctuation ...
3
votes
0answers
75 views

Potts model and model selection

Suppose to have two vectors of random variables $\mathbf{x}=(x_1,\dots,x_n)^{\prime}$ and $\mathbf{y}=(y_i,\dots,y_n)^{\prime}$, observed over a two dimensional space domain. Let ...
0
votes
0answers
20 views

Using Proc distance with a very sparse matrix

I have a large sparse data set and I would like to apply segmentation of my customers. To give you an idea, I have more than 100 variables and 2.2 mln rows. Breakdown of my variables are as follows: ...
1
vote
0answers
52 views

CRF or MRF energy functions for image segmentation

I am currently working on image segmentation for the purposes of computer vision. I have read many papers and a few books dealing with MRFs and CRFs for computer vision. All of them define an energy ...
1
vote
0answers
62 views

Cost function for image segmentation

I am currently working on image segmentation based on superpixels. My input is a data matrix that contains stixels (rectangular superpixels that span an entire column). In the matrix I have stixel ID, ...
1
vote
0answers
25 views

Classifying according to relationship between variables

I do have a large dataset and would like to classify it according to the relationship between some variables. I do not want to use clusters, because clustering results groups that are similar. I do ...
0
votes
0answers
11 views

Why is Pott's pairwise model always used?

I have been going through some literature in semantic segmentation. Authors have worked on generating probability maps as unary potential for their CRF framework, but the pairwise potential is kept as ...
0
votes
0answers
135 views

Pixel-to-pixel training in fully convolution network

I am trying to understand this paper on semantic segmentation. Here, they have trained a network end-to-end and pixel-to-pixel. I am unable to understand the network architecture. They are taking an ...
3
votes
1answer
91 views

Identify region of interest in image

I'm currently trying to work on the challenge https://www.kaggle.com/c/noaa-right-whale-recognition; I've done basic image recognition work before (Identifying plankton), but this particular challenge ...
3
votes
3answers
137 views

How to classify customers by those who use quite a lot of shops vs. mostly one specific shop

I would be interested in how to approach the following problem: A supermarket chain has 1 million customers in a region and 10 shops. For each of the customers we know the distribution for all the ...
1
vote
3answers
291 views

segmentation of univariate irregular time series

this is my first post. I have an irregular time series that exhibits large shifts in both mean and in the direction of the trend. It looks something like this (though this is far cleaner than ...
0
votes
0answers
40 views

Cluster users activity log into group sessions

I have data of user activity, each records has user id and activity time. I want to separate the users into groups along the time dimension, i.e. find groups of users that where active together around ...
2
votes
0answers
28 views

Profiling survey respondents with both categorical and ordinal variables

I have a mixture of categorical and ordinal variables from a survey that I am trying to use to create "profiles" or segments that differ from one another with respect to a dependent variable (the ...
0
votes
0answers
16 views

Is there better method to model this scenario of finding most suitable people for campaign?

I have a scenario like this: There is a population which is divided into members/non-members for one particular credit card. Based on studying the characteristics of members, we need to identify the ...
1
vote
0answers
110 views

Interpretation of cross validation results when comparing models

I'm trying to solve a bio-medical image segmentation problem using a binary classifier and then a spatial smoothing (assuming continuous regions). I have: Training set of 10 3D scans, a total of ~30 ...
13
votes
3answers
455 views

How can I programmatically detect segments of a data series to fit with different curves?

Are there any documented algorithms to separate sections of a given dataset into different curves of best fit? For example, most humans looking at this chart of data would readily divide it into 3 ...
0
votes
0answers
19 views

How can classification hypotheses be combined for segmentation?

I am the author of write-math.com, an on-line handwritten (mathematical) symbol recognizer. I would like to adjust the software so that it is able to classify complete formulas. I've used a multilayer ...
2
votes
1answer
147 views

Estimating the best length of n-gram

I have a long sequence of words or letters {word1 word2 word3 word1 word1 word2 ..etc}. Lets say we extract all the ngrams (unigrams, bigrams, trigrams, 4-gram, 5-gram ....) along with their frequency ...
2
votes
0answers
22 views

Clustering stream of new customers based on future potential

I need to cluster new customer according to their future potential, but I have only information about their first transaction. I have access to all transactions for the other customers. So I can do ...
0
votes
1answer
180 views

How is survey respondent segmentation based on market opportunity score done in practice?

As per instructions, I have administered a survey to a sample population that for several different "jobs-to-be-done" asks the survey participants to rate the importance of the "job-tobe-done" and the ...
0
votes
0answers
24 views

Merging two different segmentation solutions into one

I have the following problem: two different segmentation analysis to do, one using needs/motivations for consuming a product and one related to general attitudes toward product category and lifestyle. ...
3
votes
2answers
133 views

Controling segmentation process in order to get usable segments

My aim is to create segments based on survey data. This in it self is quite straight forward: I use PCA to extract information from the survey answers, and then ...
0
votes
1answer
163 views

Best method to assign new customers to existing clusters after segmentation?

After segmenting customer base using k means algorithm into 5 clusters , how to assign a new customer to one of the existing 5 clusters? Matching just the mean of clusters with values of new ...
2
votes
1answer
59 views

Clustering Consumer data with over 100 variables and 50000 rows each

I am tasked with performing a clustering exercise for a consumer survey dataset with the hopes of finding distinct consumer segments. In the past, I've done it using a variety of techniques- ...
1
vote
0answers
21 views

Change in distribution of a portfolio of customers

I'm looking for some high-level thoughts on understanding a change in distribution for a portfolio of customers. I have a file with information on a bunch of customers. These customers are purchasing ...
2
votes
2answers
2k views

How to use both binary and continuous variables together in clustering?

I need to use binary variables (values 0 & 1) in k-means. But k-means only works with continuous variables. I know some people still use these binary variables in k-means ignoring the fact that ...
5
votes
1answer
396 views

Clustering data into bins of variable sizes

I'd like to build a model (in R or excel) that takes in large amount of linear data and segments it into "bins". The linear data is an attribute that reflects what condition that section/record is at. ...
1
vote
1answer
307 views

Why is k-medians typically used with Manhattan rather than Euclidean distance?

K-medians is typically used with Manhattan distance rather than Euclidean distance. Why is this?
0
votes
1answer
174 views

Question of unary term (data term) of the graph cut method

I am trying to apply graph cut method for my segmentation task. I found some example codes at Graph_Cut_Demo. Part of the codes are showing below ...
0
votes
0answers
41 views

Conceptual question on image pattern representation

I have a basic question regarding pattern learning, or pattern representation. Assume I have a complex pattern of this form, could you please provide me with some research directions or concepts that ...
1
vote
0answers
82 views

Goodness of fit of linear model for Segmentation of GPS positions time series

I have some GPS coordinates series taken in regular time steps and I need to verify whether some chunks of the trajectories fit well as a straight line or not. The aim is to perform segmentation on ...
1
vote
2answers
1k views

Segmentation using cluster analysis in SPSS

I am doing a segmentation project and am struggling with cluster analysis in spss right now. Could you please help me get this answered: How do I determine the quality of the clustering in spss? In ...
2
votes
4answers
645 views

Hints on this computer vision / machine learning problem

I've been working for a while on a pet problem. The task is to identify and segment out the dark lines and possibly the wiggly ones too. I'm not looking for anyone to solve this problem for me...I'm ...
0
votes
1answer
1k views

3-4-5 Rule How to partition the sets?

In Data Mining course, we are taking 3-4-5 Rule to segments the data uniformly. I'm trying to understand these lines below, and how they are linked to the graph below too. If an interval covers ...
6
votes
1answer
179 views

Use a clustering as a segmentation

I ran a cluster analysis on a population of customers. I used variables like: Lifetime Spent amount etc. Now I'd like to use these clusters ('Little buyer', 'Regular fan of the brand A', ...) for ...
6
votes
2answers
3k views

Differences between clustering and segmentation

I have read about piecewise aggregate approximation (PAA) mining time series data, sliding window, top down and bottom up approaches for time series segmentation but these are applicable to single ...
0
votes
0answers
54 views

Error in an article with a conditional probability?

I’ve recently read the article "Visual Tracking of Human Visitors under Variable-Lighting Conditions for a Responsive Audio Art Installation," A. Godbehere, A. Matsukawa, K. Goldberg, American Control ...
2
votes
0answers
96 views

What form of analysis should be used for loss given default estimates?

I am working on BASEL II IRB models and we have to estimate loss based on historic defaults. There are different outcomes/scenarios we have identified that a default can encounter that will affect ...
1
vote
1answer
382 views

How to perform Normalization on Call Details Record to perform k-Mean Clustering

I'm new to data mining and currently doing mining project on telecom customer segmentation (based on profile and call details record). I have gender, age, call time and call duration and have to ...