Refers to techniques for classifying data into categories based on similarities (which can either be known previously, or learned).

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How to calculate false accept and reject rates in pattern recognition?

I am working on a vein pattern recognition project based on SURF algorithm and Euclidean distance. I have completed my program to find the maximum and minimum distance between vein features and find a ...
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16 views

Given 3 discriminant functions I was able to classify 2D patterns, but how do I plot decision boundaries via matplotlib?

I have implemented the discriminant function and was able to classify the 2D patterns (via Python), but I have troubles thinking about an approach to plot the decision boundaries. Hope anyone has an ...
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1answer
44 views

How to define the maximum k of the kNN classifier?

I am trying to use kNN classifier to perform some supervised learning. In order to find the best number of 'k' of kNN, I used cross validation. For example, the following codes load some Matlab ...
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1answer
45 views

Cascade Combination of Kernel Functions

I have a question regarding machine learning and specifically kernel functions. Suppose we have a Kernel function, say $K(x)$, and also another distinct one, say $K'(x)$. I want to know is $K(K'(x))$ ...
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9 views

Measuring the standard deviation in Pattern recognition

Sometimes in pattern recognition say Character recognition, Hamming distance is used although there are other distance measures. But if the pattern is represented in (1,0,-1) then Hamming distance is ...
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17 views

Linear Discriminant Analysis matrix dimension

I am trying to implement Linear Discriminant Analysis for face recognition. I have 3 classes and each classes have 10 image each. The dimension of matrix in class A, B and C is 10*500 .So each row ...
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28 views

Within scatter matrix linear discriminant analysis

I am trying to implement Linear Discriminant Analysis. I have 10 classes and each class has 3 observations at various instances: ...
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36 views

anomaly detection on logs data

I wonder , if someone know the open source anomaly detection algorithm on computer log ? For an example , computer log look like as mentioned below : "value UL-CCCH-Message ::= { integrityCheckInfo { ...
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23 views

Normalized cross correlation vs Euclidean distance in template matching

What is the difference between normalized cross-correlation and Euclidean distance in pattern recognition? -- especially if we want to do recognition with template matching. I understand about ...
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22 views

Distance calculation for Incremental sequence matching

Euclidean distance for 1D between every point in $n$ time instants located at $ X_1 = (x_1(t), x_1(t+1), x_1(t+3), ... , x_1(n))$ and $ Y_1 = (y_1(t), y_1(t+2), y_1(t+3), ... , y_1(n))$, respectively, ...
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1answer
52 views

How to interpret the number of k in k-nearest-neighbour classifier?

I have done some classification work using a k-nearest-neighbour classifier (kNN). And the classification performance is evaluated using cross-validation method. Some testing code from Matlab Help are ...
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2answers
129 views

The difference of kernels in SVM?

Can someone please tell me the difference between the kernels in SVM: Linear Polynomial Gaussian (RBF) Sigmoid Because as we know that kernel is used to mapped our input space into high ...
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1answer
41 views

Feature selection for pattern mining

I must find frequent patterns in temporal data, using a method that was imposed to me. This tool has problems handling these data: processing is long and takes a lot of memory. So, I would like to ...
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14 views

Reference Request: Human speech extraction using Machine Learning

I am trying to extract human voice from a noisy clip and studied some test upon it like, voice clipping using deep learning or MLP ann etc., then speech identification using a sequence based ...
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65 views

Pattern Recognition in Practical Problem in R

I am using R for last 4 months with basic test analysis, regression models, ANOVA etc. Now I am looking into a particular problem. In words problem can be stated like, A particular machine got a ...
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319 views

Can machine learning find all sort of crazy connections?

If you try a real thoroughly won't a computer find all sort of silly patterns? Messages from ETs in the bible rainy Sundays in China or Australia -> the chances of your sport team win reading many ...
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28 views

Bayesian parameter estimation homework problem

For BPE approach,for p($\theta$)~U(0,1) show that p(x|D)= $1/n+2[(x+ \sum_{k=1}^n(x_k)!)$ $ (n+1-x-$($\sum_{k=1}^n(x_k)$!]$/$[$(\sum_{k=1}^n(x_k))$! $(n-\sum_{k=1}^n(x_k))$!] I have tried using the ...
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1answer
36 views

Question about computing Bayes Error - with or without loss function?

I am new to Bayesian Decision Theory and don't understand the following concept: So from what I understood, the Bayes error is used to report the performance of a Bayes classifier in terms of the ...
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30 views

Feature selection methods comparison

I recently run a project that involves a feature selection step before further pattern recognition. The number of features for our data set is very large and instead of running greedy ...
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48 views

Finding the best path through the matrix in DTW

I have two time series q and c and I want to calculate dynamic time wrapping (DTW) distance between these two time series: ...
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1answer
58 views

Recovering true data from multiple noisy versions

I am trying to find if there is any way to get the true data from multiple noisy versions, but the true data has a peculiar property. Problem Statement Consider a matrix $F=[f_1, f_2, ... , f_n]$ ...
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33 views

statistical test for sequence of data

There is a sequence of data. It might have different types of trend, i.e., increasing, decreasing, and even cycling pattern. But there is an assumption that these trends should be smooth. (maybe not ...
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58 views

Pattern detection in a time series

Lets say I am trying to find patterns in pricing of a commodity such as corn and I have monthly time series data on the demand, the temperature, cost of water, and the current market supply. What ...
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29 views

Patterns in binary data sorted with rank indices

I have a sequence of binary data, each row of which has seemingly random bits and associated with an integer value ("rank"). When we have a binary datum, we always can calculate the rank related to it ...
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2answers
97 views

How to mine the “customers who bought X also bought Y” type of correlation?

I am looking for a statistical model to detect grouping patterns among a population X of n element with respect to their association with k elements of population Y. In modern marketing, an example ...
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1answer
44 views

How do I calculate a probability to encounter a pattern of numbers in a numbers list? [duplicate]

Imagine you have an array of integer numbers. You need to calculate the probability of encountering some integer sub-array in that list. For example: the original list: ...
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1answer
95 views

Poorness of Kernel methods on visual pattern recegnition?

I am currently reading the recent papers mainly written by Y. Bengio [1],[2],[3]. There are very strong claims about poorness of Kernel methods on recognizing handwritings in many general cases but ...
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218 views

Automated approach to find patterns and correlations between multiple sets of data

I'm trying to find a correlation or repeated patterns between several sets of data, at this stage 15, but I plan to expand this to several hundred data sets. At the moment I am plotting the data in ...
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1answer
72 views

Pattern classificaton using neural network learning

Paper1 (freely available) and Paper2 (Springer) talk about application of fuzzy cognitive map (FCM) for pattern classification. I am having a tough time to understand how the equation of FCM is ...
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32 views

Nod and shake detection

I am trying to build a system to automatically detect head nods and shakes in videos. I have reliable eyes position information at each frame and I'd like to use the info to perform the detection of ...
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2answers
100 views

Which statistical method to use for finding systematic patterns in data

As part of a broader study I am analysing 30 websites that fall into 3 categories: Consumer (10 sites) Commercial (10 sites) Health (10 sites) The approach I used was a 'tick and flick' ...
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57 views

Parameter space exploration

I do realise this question is quite specific and practical, but I seek for some general help which helps me progress further in my analysis. Let $y(\boldsymbol{x})\in\mathbb{R}$ be the function I'd ...
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2answers
221 views

Analysis of temporal patterns

I am analysing data on events that I have categorized into groups. So, for instance, say I have 3000 events categorized into 5 groups, which we call A to E. I will have something like ...
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1answer
636 views

Why is Mantel's test preferred over Moran's I?

Mantel's test is widely used in biological studies to examine the correlation between the spatial distribution of animals (position in space) with, for example, their genetic relatedness, rate of ...
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1answer
73 views

Find music tempo with a audio signal

I'd like to know if there is statistical techniques that aims to find the rhythm/tempo of a music based on audio signal :
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47 views

Question about autocorrelation and covariance matrix

I have two questions. they are problems form K. Fukunaga's Introduction to Statistical Pattern Recognition: First: Prove inverse of $S \cdot M$ (mean vector) is a similar vector to inverse of ...
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36 views

Recognition of household objects ( image processing, pattern recognition ) using wide lens?

Camera setup: We have setup some stereo cameras in a living apartment. That is, the indoor environment is monitored. With the stereo cameras, wide lens (3.5mm) are used to cover a big volume. The ...
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1answer
118 views

Finding correlation, triggers and patterns between two (or more datasets)

I am trying to find correlations between multiple data sets, for this example i am using two pieces of data, the closing stock price for Coca-Cola and Pepsi for the last year. I've been pointed in ...
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243 views

Is there any alternative to HMM?

I've been using Hidden Markov Models (HMM) for some time. Now I would like to know about any other statistical model that can prove to be as useful as HMM. For example I was exploiting HMM for gesture ...
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1answer
151 views

How to test periodical patterns of events in a timeline

Imagine the situation: there is a lecture of a famous scientist in auditorium which begins in - say 9:00. If students do not arrive in time - the door to auditorium will be closed and nobody allowed ...
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37 views

How can I measure separability between different number of instance of one feature vector?

How can I measure separability between different number of instance of one feature vector? For example the main vector is V=[1 1 2 3 4 5 7 8 10 100 1000 99 999 54] ...
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131 views

Why is Moran's I not equal to “-1” in perfectly dispersed point pattern

Is wikipedia wrong...or I don't understand it? Wikipedia: The white and black squares ("chess pattern") are perfectly dispersed so Moran's I would be −1. If the white squares were stacked to one ...
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1answer
199 views

identifying events (patterns) that occur before an event of interest using sequence of events data

I'm interested in identifying events (patterns) that occur before an event of interest. For example, a customer calls in to complain or a customer checks their balance online then the customer closes ...
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99 views

Probabilistic latent semantic analysis vs bag of words

I am going through probabilistic latent semantic analysis (pLSA) for image classification. I did some image classification experiments with BOW (bag of words) and pLSA but based on my experiments BOW ...
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1answer
56 views

Conceptual question on pattern recognition

I am just a beginner in machine learning and finding tough time to understand few concepts. I have 10 strings of characters of length 50 each. These are the training data $T(i)$ for $i=1:10$. The ...
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28 views

How to built a software recognition algorithm

I'm trying to design an algorithm to determine which softwares are installed on a computer. I have several millions of files each corresponding to the list of softwares which are on a computer. I've ...
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1answer
150 views

Different number of samples (observations) per class (one vs. all classification)

I have 20 observations labeled for each class. The number of classes is 5, so I have a total of 100 observations. I want to classify one class vs. other classes (one vs. all). For this, I first ...
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414 views

How to use Gaussian mixture model for multivariate pattern classification

I am new to statistical pattern recognition and trying to learn.To begin with I am trying to work with two class problems and trying to classify motion activities as mentioned in the paper "Object ...
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59 views

Finding temporal patterns that predict “life length”

I'm doing research on system usage. It is an online system that provide certain information to users, and I want to predict for how long users use the system. I already noticed that if people don't ...
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206 views

The derivation of the Mahalanobis distance formula [closed]

I recently asked about the Mahalanobis distance and I got pretty good answers in this post: Bottom to top explanation of the Mahanalobis distance? I think I got the idea, but what I still felt ...