Questions tagged [novelty-detection]

The tag has no usage guidance.

Filter by
Sorted by
Tagged with
17
votes
3answers
27k views

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?
6
votes
3answers
724 views

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 ...
6
votes
1answer
184 views

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 ...
4
votes
2answers
8k views

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 ...
4
votes
1answer
1k views

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=...
2
votes
2answers
260 views

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 ...
2
votes
1answer
5k views

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 ...
1
vote
1answer
4k views

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 ...
1
vote
1answer
81 views

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 <...
1
vote
2answers
2k views

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
vote
0answers
68 views

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\...
0
votes
1answer
919 views

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"...
0
votes
0answers
49 views

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.
0
votes
1answer
31 views

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 ...
0
votes
0answers
16 views

Choosing parameters for Clifton Extreme-Value-Theory(EVT) novelty detection technique

I was reading your Clifton et all artibles about applying Extreme-Value-Theory(EVT) for novelty detection, eg: http://www.robots.ox.ac.uk/~davidc/pubs/mevt2010.pdf and it looks like one needs to ...
0
votes
0answers
51 views

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 ...
0
votes
0answers
740 views

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 ...