Questions tagged [anomaly]

The tag has no usage guidance.

Filter by
Sorted by
Tagged with
0 votes
1 answer
13 views

How to find an anomalous matrix among many?

Let's say we have a bunch of matrices that we know are non-anomalous. We now receive a new matrix and want to know if it belongs into the group or is way off. Is there a way to do that? I'm thinking ...
user avatar
0 votes
0 answers
23 views

What type of Anomaly Detection Model could I use?

I would like to create an anomaly detection model that assigns a probability of risk instead of labels (1 or 0). My problem is that I only know for sure which records are anomalous but not which are ...
user avatar
0 votes
1 answer
31 views

Assign a risk score in records in a dataset

I was wondering, if I have a dataset with categorical and numerical data and labels such as 1 or 0 that shows if a row is anomalous or normal respectively. Is it possible to create somehow a model ...
user avatar
0 votes
1 answer
18 views

Anomaly Detection Techniques

Often the hardest part of solving an Anomaly Detection problem can be finding the right technique for the job. Different Anomaly techniques are better suited for different types of data and different ...
user avatar
  • 2,301
0 votes
0 answers
16 views

Generation of Anomalous data points

I have a task to generate some anomalous points in a real world dataset with 15 features, and a synthetic dataset of 5 features. I was thinking of using correlation between features, but it'll be a ...
user avatar
1 vote
1 answer
95 views

How to detect anomalies in each feature - time series

I have a dataset with 5 features corresponding to 5 sensors that measure each three seconds the state of an accelerator. It is structured as well: ...
user avatar
  • 43
1 vote
2 answers
55 views

How do I determine the top "reason" for anomaly when using Isolation Forests

I am using Isolation Forests for Anomaly Detection. Say, my set has 10 variables, var1, var2, ..., var10, and I found an anomaly. Can I rank the 10 variables var1, var2, ..., var10 in such a way I can ...
user avatar
  • 1,851
0 votes
1 answer
39 views

which statistical parameters are more useful to detect anomalies and outlier? mean max min var?

This time series contains some time frame which each of them are 8K (frequencies)*151 (time samples) in 0.5 sec [overall 1.2288 millions samples per half a second) I need to find anomalous based on ...
user avatar
  • 1,516
0 votes
0 answers
62 views

How is convex hull method used in outlier detection?

I think the slides are bit unclear on what they want to say. Can someone elaborate this with example.
user avatar
1 vote
1 answer
45 views

How to test unsupervised learning methods for anomaly detection?

How to test unsupervised learning methods for anomaly detection? I am looking for a test strategy to evaluate my result of my anomaly detection technique? what is your offer more than evaluate with ...
user avatar
  • 1,516
1 vote
1 answer
25 views

Practical problems in anomaly detection where the number of normal data is extremely high compared to abnormal data

If the ratio of abnormal data is about 1 to 10,000 normal data, even if the true negative rate is 99%, there will be 100 false positive data, and the precision( TP/(TP+FP) ) will be low. If this kind ...
user avatar
  • 111
3 votes
1 answer
60 views

How to determine the abnormality of a specific variable by taking into account all the other variables in the data?

I have an issue of machine learning/anomaly detection. Indeed, I have a variable Y and several other variables X. The purpose is to quantify the degree of abnormality of the data on Y but I have to ...
user avatar
  • 31
2 votes
2 answers
41 views

How to perform Anomaly Detection on a force profile?

I have a set of force profiles of an industrial machine. I'm trying to develop an algorithm that tries to understand when a new profile is "anomalous" with respect to the ones in "...
user avatar
  • 21
0 votes
2 answers
48 views

Are cluster feature and micro-cluster good summary statistics for outlier detection in high dimensional data streams?

I'm dealing with outlier detection in data streams. I'm looking for a way to summarize my data and obtain important statistics such as means and variance, etc. I want to know if the cluster features ...
user avatar
  • 51
1 vote
1 answer
64 views

Anomaly Detection System

I need a sanity check. I want to create an anomaly detection system. The logic which I am planning to use is the following: Find anomalies in the past using Seasonal Hybrid Extreme Studentized ...
user avatar
  • 13
1 vote
0 answers
64 views

How to find anomalies/outliers in Panel Data?

I have panel data based on 900000 different entities with 384 time steps and the data is not normally distributed. I am looking for outliers/anomalies, this is unsupervised as I have no examples of ...
user avatar
4 votes
2 answers
249 views

Anomaly detection without any knowledge about structure

I have an interesting question, my code needs to be able to handle structured data where I don't know much about the structure at development time. I know the samples follow a schema that can be ...
user avatar
0 votes
1 answer
273 views

Anomaly Detection for Large Time Series Data [closed]

I am working on detecting anomalies within a large time series data set. It is updated on a regular basis and consists of more than 30 parameters. I am using R as a reference language. It is a first ...
user avatar
  • 3
22 votes
4 answers
21k views

Looking for a good package for anomaly detection in time series

Is there a comprehensive open source package (preferably in python or R) that can be used for anomaly detection in time series? There is a one class SVM package in scikit-learn but it is not for the ...
user avatar
  • 1,207
1 vote
4 answers
489 views

How to detect anomalous points

As is clear from the figure, the blue points, which don't follow the trend, are anomalous points. I'm wondering about the best non-parametric method to detect those points. I have tested some ...
user avatar
  • 443
2 votes
1 answer
7k views

How to improve precision under imbalanced classification

I am using an imbalanced dataset (rare positive cases) to learn models for prediction and the final good AUC is 0.92 but the F1 score is very low0.2. Is it possible to add some key features which ...
user avatar
  • 753