Questions tagged [novelty-detection]
The novelty-detection tag has no usage guidance.
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What is the relationship between bias-variance and sensitivity-specificity for novelty detection?
An over or under-parameterized binary classification model (- vs +) tends to over or under-fit (bias-variance tradeoff). This leads to errors during prediction on unseen data. Depending on if ...
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One class SVM and centered data
I understand that the one class SVM try to separate the normal training data point from the origin.
My guess is that, if we centered the data in a normalisation step, the OCSMV will works poorly since ...
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How to tune parameters for novelty detection with only normal dataset
There exists multiple novelty detection methods. I'll discuss two:
One-class SVM
LOF
Both of them have parameters. For example, the SVM has a $\nu$ parameter and if the SVM uses the RBF kernel, it ...
- 113
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novelty detection to prevent prediction outside training dataset
I have a training dataset composed of $d$ independent variables $\bf X$ and a dependent variable $\bf y$ for $n$ observations. I have trained a model with this $n$ observations.
What I want to do now ...
- 21
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Is it better to do per-class anomaly detection on P(x, y) or P(x | y)?
(Not an expert in anomaly detection.)
I'd like to experiment with per-class anomaly detection.
That is, we have a feature vector $x$, and a classifier that predicts its class $\hat{y}$. I'd like to ...
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if the Seasonal Hybrid ESD (S-H-ESD) algorithm can be used even when seasonal does not exist
First, I have monthly data from January 2000 to January 2020. However, seasonality does not appear. I wonder if S-H-ESD algorithms can be used even in this case.
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Can I use anomaly detection models as outliers and novelty detection?
Several books that I have read do not distinguish the several models that exist for anomaly and outlier detection.
After I read about these models, I have chosen to detect anomalous events on ...
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Is it OK to have only a single class labels in test data for prediction with one-class-svm?
I have a data which has only a single class, namely, '0'. There is no 'not 0' class.
The one-class SVM model was trained on a <...
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How to choose a method for binary classifier based on only positive and unlabelled examples?
I need to build a binary classifier with machine learning, as I fail to manually choose a combination of features to achieve minimal fraction of false positives.
What is best practice for choosing a ...
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Detecting changes in large number of time-series that share seasonality
I have large number of time-series that are independent of each other, but share some seasonality patterns. I need to detect anomalies/changes (increased volume, change in mean), that appear in the ...
Tim♦
- 134k
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Weighting loss function using Voronoi-tessellation of response space
Let's say you have some Real-valued features $\mathbf{X}$ and Real-valued univariate responses $\mathbf{y}$. We want to fit a regression model to this data:
$$\mathbf{y} = f\left(\mathbf{X};\beta\...
user145807
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Best way to train one-class SVM
Let`s say I have training data which contains 10 classes and have build a classifier using this data.
When applying this classifier in real life it may encounter examples not belong to the classes ...
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Are Novelty Effects accounted for in Power Analysis?
I'm a bit a new hypothesis testing, so I hope that this question makes sense. Say that I proposed a new treatment (like a new drug or something) and I wanted to test whether this drug was effective or ...
user46925
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Parameter optimization in one-class SVM of LibSVM
I am new to machine learning and SVMs. I have a general question regarding the optimization of parameters in one-class SVM in libsvm in R. I found similar posts but yet not conclusive answer. Can ...
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Is a one class naive bayes possible?
I have a simple question - I think.
I have recently read a paper:
https://www.google.co.uk/url?sa=t&source=web&rct=j&url=http://www.cs.columbia.edu/~kewang/paper/DMSEC-camera.pdf&ved=...
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Time series analysis (removing effect of external factor)
I'm currently working on detecting the response from a sensor with the following profile:
The sensor responds to temperature fluctuations and I was wondering if y'all could suggest methods to "remove"...
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Power martingales for change detection: M goes to zero?
I'm trying to apply the power martingale framework by [Vovk et al., 2003] to change detection in unlabeled data streams, just like in [Ho and Wechsler, 2007]. The basic idea involves using a power ...
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Novelty and Outlier Detection in Unsupervised Learning Style
Currently I am looking for some method to do novelty and outlier detection. I found some good example here using scikit-learn (Link1). However, it is based on supervised learning and I believe the ...
- 1,709
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Novelty and Outlier Detection for Multi-label Data
I met a problem of using novelty and outlier detection for my multi-label data. For example, I have got some training data that is not polluted by outliers. However, the training data are with multi-...
- 1,709
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Clustering based anomaly detection
I'm trying to implement anomaly detection based on clustering. I'm hopping for confirmation of my approach, and I'm exposing my idea, being aware that I could have miss something in my analysis, so ...
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What is one class SVM and how does it work?
I was using one class SVM, implemented in scikit-learn, for my research work. But I have no good understanding of this.
Can anyone please give a simple, good explanation of one class SVM?
