Linked Questions

1
vote
2answers
1k views

A better Outlier Detection approach! [duplicate]

Currently I am using Cook's distance to detect outliers in multivariate data. Is there any better approach than Cook's distance for the same?
0
votes
0answers
967 views

How to detect outliers? [duplicate]

I have a matrix where the rows are the data points (samples) and the columns are the features (predictors). Let's say I have 1000 data points and 20 features, i.e. the matrix is of size 1000 x 20. ...
2
votes
1answer
639 views

Detect outliers in multi dimensions [duplicate]

I tried to implement outlier detection for one dimension using inter quartile. For instance, a given variable cost or revenue or profit. but I'm missing outliers in other dimensions when running for ...
1
vote
0answers
153 views

What are the methods for multivariate outlier detection? [duplicate]

I have to work with research paper using multivariate outlier detection methods. Please list the methods for multivariate outlier detection and give some suggestions and ideas....
0
votes
0answers
36 views

Outlier detection in high dimensional data [duplicate]

I am looking to clean up a large data set (~300) with a large number of features (~140). I would like to explore outliers in the data. My first thought was to use PCA to reduce these features to a ...
44
votes
8answers
10k views

Rigorous definition of an outlier?

People often talk about dealing with outliers in statistics. The thing that bothers me about this is that, as far as I can tell, the definition of an outlier is completely subjective. For example, ...
14
votes
5answers
29k views

Is there a simple way of detecting outliers?

I am wondering if there is a simple way of detecting outliers. For one of my projects, which was basically a correlation between the number of times respondents participate in physical activity in a ...
24
votes
1answer
5k views

What are the multidimensional versions of median [duplicate]

What are the multidimensional versions of the median and what are their pros and cons? I confess this doesn't have a single answer, but I think it is a useful question to ask and will be a benefit to ...
11
votes
3answers
3k views

Finding the average GPS point

I need to write a program to find the average GPS point from a population of points. In practice the following happens: Each month a person records a GPS point of the same static asset. Because of ...
10
votes
2answers
7k views

Anomaly detection: what algorithm to use?

Context: I'm developing a system that analyzes clinical data to filter out implausible data that might be typos. What I did so far: To quantify the plausibility, my attempt so far was to normalize ...
7
votes
3answers
5k views

How to find quantiles for multivariate data using R?

Quantile for a single variable is easy to implement in R. However, it is not an easy task to quantile for multivariate data. There are several papers have been proposed to quantile for multivariate ...
2
votes
3answers
2k views

Identifying outlier data in high-dimensional settings

I have a data set with high-dimensional feature space. Are there any pre-processing methodologies that can detect outliers from this data set? The outlier, I mean, are the ones that tend to be very ...
7
votes
1answer
1k views

Does Pearson correlation require removal of bivariate or univariate outliers?

Does the Pearson's correlation estimator require no bivariate outliers, or no outliers in each of two individual vectors of data? The answer will impact on how I winsorize outliers before calculating ...
5
votes
1answer
4k views

Test for bivariate outliers

I have been given a set of data points $(x_i,y_i)$. I have to plot a scatter plot and determine if there are any outliers. But I haven't been taught a method to measure which data point is an outlier ...
11
votes
2answers
2k views

Robust multivariate Gaussian fit in R

I need to fit a generalized Gaussian distribution to a 7-dim cloud of points containing quite a significant number of outliers with high leverage. Do you know any good R package for this job?

15 30 50 per page