Abstract During analysis of scientific research data, it is customary to encounter anomalous values or missing data. Anomalous values can be the result of errors of recording, typing, measurement by instruments, or may be true outliers. This review discusses concepts, examples and methods for identifying and dealing with such contingencies. In the case of missing data, techniques for imputation of the values are discussed in, order to avoid exclusion of the research subject, if it is not possible to retrieve information from registration forms or to re-address the participant.

Identifying and dealing with outliers is an important part of data analysis. A new visualization, the O3 plot, is introduced to aid in the display and understanding of patterns of multivariate outliers. It uses the results of identifying outliers for every possible combination of dataset variables to provide insight into why particular cases are outliers. The O3 plot can be used to compare the results from up to six different outlier identification methods. There is anRpackage OutliersO3 implementing the plot. The article is illustrated with outlier analyses of German demographic and economic data. Supplementary materials for this article are available online.

When we talk about the features to predict the sex of each person, it is undeniable that Height & Weight are typical features for that.

This dataset is purposely for the beginner who recently has done studying Machine Algorithm and may want to apply their algorithm on a simple dataset.

There are just 2 features (Height, Weight) & 1 label (Sex)

Height (inches) Weight Sex (male | female)

This is a outlier free data set for regression modelling.

ABSTRACT The considerable volume of data generated by sensors in the field presents systematic errors; thus, it is extremely important to exclude these errors to ensure mapping quality. The objective of this research was to develop and test a methodology to identify and exclude outliers in high-density spatial data sets, determine whether the developed filter process could help decrease the nugget effect and improve the spatial variability characterization of high sampling data. We created a filter composed of a global, anisotropic, and an anisotropic local analysis of data, which considered the respective neighborhood values. For that purpose, we used the median to classify a given spatial point into the data set as the main statistical parameter and took into account its neighbors within a radius. The filter was tested using raw data sets of corn yield, soil electrical conductivity (ECa), and the sensor vegetation index (SVI) in sugarcane. The results showed an improvement in accuracy of spatial variability within the data sets. The methodology reduced RMSE by 85 %, 97 %, and 79 % in corn yield, soil ECa, and SVI respectively, compared to interpolation errors of raw data sets. The filter excluded the local outliers, which considerably reduced the nugget effects, reducing estimation error of the interpolated data. The methodology proposed in this work had a better performance in removing outlier data when compared to two other methodologies from the literature.

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Anomaly Detection Market Size 2025-2029

The anomaly detection market size is valued to increase by USD 4.44 billion, at a CAGR of 14.4% from 2024 to 2029. Anomaly detection tools gaining traction in BFSI will drive the anomaly detection market.

Major Market Trends & Insights

North America dominated the market and accounted for a 43% growth during the forecast period.
By Deployment - Cloud segment was valued at USD 1.75 billion in 2023
By Component - Solution segment accounted for the largest market revenue share in 2023

Market Size & Forecast

Market Opportunities: USD 173.26 million
Market Future Opportunities: USD 4441.70 million
CAGR from 2024 to 2029 : 14.4%

Market Summary

Anomaly detection, a critical component of advanced analytics, is witnessing significant adoption across various industries, with the financial services sector leading the charge. The increasing incidence of internal threats and cybersecurity frauds necessitates the need for robust anomaly detection solutions. These tools help organizations identify unusual patterns and deviations from normal behavior, enabling proactive response to potential threats and ensuring operational efficiency. For instance, in a supply chain context, anomaly detection can help identify discrepancies in inventory levels or delivery schedules, leading to cost savings and improved customer satisfaction. In the realm of compliance, anomaly detection can assist in maintaining regulatory adherence by flagging unusual transactions or activities, thereby reducing the risk of penalties and reputational damage.
According to recent research, organizations that implement anomaly detection solutions experience a reduction in error rates by up to 25%. This improvement not only enhances operational efficiency but also contributes to increased customer trust and satisfaction. Despite these benefits, challenges persist, including data quality and the need for real-time processing capabilities. As the market continues to evolve, advancements in machine learning and artificial intelligence are expected to address these challenges and drive further growth.

What will be the Size of the Anomaly Detection Market during the forecast period?

Get Key Insights on Market Forecast (PDF) Request Free Sample

How is the Anomaly Detection Market Segmented ?

The anomaly detection industry research report provides comprehensive data (region-wise segment analysis), with forecasts and estimates in 'USD million' for the period 2025-2029, as well as historical data from 2019-2023 for the following segments.

Deployment

  Cloud
  On-premises


Component

  Solution
  Services


End-user

  BFSI
  IT and telecom
  Retail and e-commerce
  Manufacturing
  Others


Technology

  Big data analytics
  AI and ML
  Data mining and business intelligence


Geography

  North America

    US
    Canada
    Mexico


  Europe

    France
    Germany
    Spain
    UK


  APAC

    China
    India
    Japan


  Rest of World (ROW)

By Deployment Insights

The cloud segment is estimated to witness significant growth during the forecast period.

The market is witnessing significant growth, driven by the increasing adoption of advanced technologies such as machine learning algorithms, predictive modeling tools, and real-time monitoring systems. Businesses are increasingly relying on anomaly detection solutions to enhance their root cause analysis, improve system health indicators, and reduce false positives. This is particularly true in sectors where data is generated in real-time, such as cybersecurity threat detection, network intrusion detection, and fraud detection systems. Cloud-based anomaly detection solutions are gaining popularity due to their flexibility, scalability, and cost-effectiveness.

This growth is attributed to cloud-based solutions' quick deployment, real-time data visibility, and customization capabilities, which are offered at flexible payment options like monthly subscriptions and pay-as-you-go models. Companies like Anodot, Ltd, Cisco Systems Inc, IBM Corp, and SAS Institute Inc provide both cloud-based and on-premise anomaly detection solutions. Anomaly detection methods include outlier detection, change point detection, and statistical process control. Data preprocessing steps, such as data mining techniques and feature engineering processes, are crucial in ensuring accurate anomaly detection. Data visualization dashboards and alert fatigue mitigation techniques help in managing and interpreting the vast amounts of data generated.

Network traffic analysis, log file analysis, and sensor data integration are essential components of anomaly detection systems. Additionally, risk management frameworks, drift detection algorithms, time series forecasting, and performance degradation detection are vital in maintaining system performance and capacity planning.

Understanding the statistics of fluctuation driven flows in the boundary layer of magnetically confined plasmas is desired to accurately model the lifetime of the vacuum vessel components. Mirror Langmuir probes (MLPs) are a novel diagnostic that uniquely allow us to sample the plasma parameters on a time scale shorter than the characteristic time scale of their fluctuations. Sudden large-amplitude fluctuations in the plasma degrade the precision and accuracy of the plasma parameters reported by MLPs for cases in which the probe bias range is of insufficient amplitude. While some data samples can readily be classified as valid and invalid, we find that such a classification may be ambiguous for up to 40% of data sampled for the plasma parameters and bias voltages considered in this study. In this contribution, we employ an autoencoder (AE) to learn a low-dimensional representation of valid data samples. By definition, the coordinates in this space are the features that mostly characterize valid data. Ambiguous data samples are classified in this space using standard classifiers for vectorial data. In this way, we avoid defining complicated threshold rules to identify outliers, which require strong assumptions and introduce biases in the analysis. By removing the outliers that are identified in the latent low-dimensional space of the AE, we find that the average conductive and convective radial heat fluxes are between approximately 5% and 15% lower as when removing outliers identified by threshold values. For contributions to the radial heat flux due to triple correlations, the difference is up to 40%.

In the R programming language, there are many packages related to a topic. Outliers is one of them. Dataset and descriptions of packages related to outliers in R:

Package_Name: Package name Update_Date: The last update date of the package Version: Package version Depend: Package Depend License: Package License Needs Compilation: Need a compilation or not? URL: The package's website Encoding: UTF-8 or not Maintainer: Package maintainer Vignette_builder: Vignette builder Title: The title of the package Downloads1month: Number of downloads in the last 1 month Downloads6month: Number of downloads in the last 6 month Downloads12month: Number of downloads in the last 12 month

The zip files contains 12338 datasets for outlier detection investigated in the following papers:

This course will introduce you to two of these tools: the Hot Spot Analysis (Getis-Ord Gi*) tool and the Cluster and Outlier Analysis (Anselin Local Moran's I) tool. These tools provide you with more control over your analysis. You can also use these tools to refine your analysis so that it better meets your needs.GoalsAnalyze data using the Hot Spot Analysis (Getis-Ord Gi*) tool.Analyze data using the Cluster and Outlier Analysis (Anselin Local Moran's I) tool.

This contains the code and data necessary to rerun the power analysis used in testing BOREALIS.

Borealis is an R library performing outlier analysis for count-based bisulfite sequencing data. It detects outlier methylated CpG sites from bisulfite sequencing (BS-seq). The core of Borealis is modeling Beta-Binomial distributions. This can be useful for rare disease diagnoses.

There are three files containing Stata data, and do and log-files. These are associated with the empirical models reported in the replication study, “Outlier Analysis: Natural Resources and Immigration Policy,” POLS ONE. Questions or comments regarding these materials should be directed to Seung-Whan Choi, Department of Political Science, University of Illinois at Chicago. His email address is whanchoi@uic.edu and his homepage address is https://whanchoi.people.uic.edu/.

There has been a tremendous increase in the volume of sensor data collected over the last decade for different monitoring tasks. For example, petabytes of earth science data are collected from modern satellites, in-situ sensors and different climate models. Similarly, huge amount of flight operational data is downloaded for different commercial airlines. These different types of datasets need to be analyzed for finding outliers. Information extraction from such rich data sources using advanced data mining methodologies is a challenging task not only due to the massive volume of data, but also because these datasets are physically stored at different geographical locations with only a subset of features available at any location. Moving these petabytes of data to a single location may waste a lot of bandwidth. To solve this problem, in this paper, we present a novel algorithm which can identify outliers in the entire data without moving all the data to a single location. The method we propose only centralizes a very small sample from the different data subsets at different locations. We analytically prove and experimentally verify that the algorithm offers high accuracy compared to complete centralization with only a fraction of the communication cost. We show that our algorithm is highly relevant to both earth sciences and aeronautics by describing applications in these domains. The performance of the algorithm is demonstrated on two large publicly available datasets: (1) the NASA MODIS satellite images and (2) a simulated aviation dataset generated by the ‘Commercial Modular Aero-Propulsion System Simulation’ (CMAPSS).

Traffic analytics, rankings, and competitive metrics for outlier.nyc as of September 2025

Dataset

This dataset was created by fehu.zone

Released under Other (specified in description)

Contents

Model Access Outlier Detection Market Outlook

According to our latest research, the global Model Access Outlier Detection market size reached USD 1.32 billion in 2024, driven by the increasing need for advanced anomaly detection in digital infrastructure. The market is projected to grow at a CAGR of 14.8% from 2025 to 2033, reaching an estimated USD 4.15 billion by 2033. This robust growth is fueled by the rising adoption of AI-based security solutions, the proliferation of complex data environments, and the urgent demand for real-time threat detection across critical industries.

The primary growth factor for the Model Access Outlier Detection market is the exponential increase in cyber threats and sophisticated attacks targeting enterprise data and networks. As organizations digitize operations, they generate vast volumes of data, making traditional rule-based security approaches inadequate. Outlier detection solutions leverage machine learning and artificial intelligence to identify unusual patterns and potential threats in real time, significantly reducing response times and minimizing the risk of data breaches. The integration of these technologies into existing security frameworks is becoming a necessity, especially in highly regulated sectors such as banking, healthcare, and government, where data integrity and privacy are paramount.

Another significant driver propelling the market is the rapid adoption of cloud computing and the proliferation of IoT devices. As businesses migrate workloads to the cloud and deploy interconnected devices, the attack surface expands, necessitating advanced outlier detection mechanisms. Cloud-based solutions offer scalability, flexibility, and centralized monitoring, making them particularly attractive for organizations with distributed operations. Furthermore, the shift towards remote work and digital collaboration has increased the demand for real-time monitoring and anomaly detection to safeguard sensitive data and ensure business continuity. The continuous evolution of AI algorithms and the availability of big data analytics further enhance the accuracy and efficiency of outlier detection systems, contributing to sustained market growth.

The growing emphasis on regulatory compliance and data protection standards worldwide is also catalyzing the adoption of Model Access Outlier Detection solutions. Stringent regulations such as GDPR, HIPAA, and PCI DSS require organizations to implement robust security measures and continuously monitor access to critical systems. Outlier detection tools play a vital role in meeting these compliance requirements by providing automated alerts, detailed audit trails, and actionable insights into suspicious activities. As regulatory landscapes become more complex, organizations are investing in advanced detection technologies not only to avoid penalties but also to build trust with customers and stakeholders.

From a regional perspective, North America currently dominates the Model Access Outlier Detection market, accounting for the largest revenue share in 2024, followed by Europe and Asia Pacific. The presence of leading technology vendors, high cybersecurity awareness, and significant investments in digital infrastructure contribute to North America’s leadership. Europe is experiencing steady growth due to stringent data protection regulations and the increasing adoption of cloud-based security solutions. Meanwhile, the Asia Pacific region is poised for the fastest growth, driven by rapid digital transformation, expanding IT ecosystems, and rising incidences of cyber threats in emerging economies. The market’s global expansion is further supported by ongoing technological advancements and the increasing integration of AI and machine learning in security operations.

Component Analysis

The Component segment of the Model Access Outlier Detection market is broadly categorized into Software and Services. Software solutions are at the core of this market, comprising advanced analytics platforms, AI-driven detection engines, and customizable dashboards. These software offerings are designed to seamlessly integrate with existing IT infrastructure, providing organizations with the capability to monitor access patterns, identify anomalies, and generate real-time alerts. The sophistication of these tools lies in their ability to adapt to evolving threat landscapes, utilizing machine learning algorithms to

Identification of features with high levels of confidence in liquid chromatography-mass spectrometry (LC MS) lipidomics research is an essential part of biomarker discovery, but existing software platforms can give inconsistent results, even from identical spectral data. This poses a clear challenge for reproducibility in bioinformatics work, and highlights the importance of data-driven outlier detection in assessing spectral outputs – here demonstrated using a machine learning approach based on support vector machine regression combined with leave-one-out cross validation – as well as manual curation, in order to identify software-driven errors driven by closely related lipids and by co-elution issues.

The lipidomics case study dataset used in this work analysed a lipid extraction of a human pancreatic adenocarcinoma cell line (PANC-1, Merck, UK, cat no. 87092802) analysed using an Acquity M-Class UPLC system (Waters, UK) coupled to a ZenoToF 7600 mass spectrometer (Sciex, UK). Raw output files are included alongside processed data using MS DIAL (v4.9.221218) and Lipostar (v2.1.4) and a Jupyter notebook with Python code to analyse the outputs for outlier detection.

Thorough knowledge of the structure of analyzed data allows to form detailed scientific hypotheses and research questions. The structure of data can be revealed with methods for exploratory data analysis. Due to multitude of available methods, selecting those which will work together well and facilitate data interpretation is not an easy task. In this work we present a well fitted set of tools for a complete exploratory analysis of a clinical dataset and perform a case study analysis on a set of 515 patients. The proposed procedure comprises several steps: 1) robust data normalization, 2) outlier detection with Mahalanobis (MD) and robust Mahalanobis distances (rMD), 3) hierarchical clustering with Ward’s algorithm, 4) Principal Component Analysis with biplot vectors. The analyzed set comprised elderly patients that participated in the PolSenior project. Each patient was characterized by over 40 biochemical and socio-geographical attributes. Introductory analysis showed that the case-study dataset comprises two clusters separated along the axis of sex hormone attributes. Further analysis was carried out separately for male and female patients. The most optimal partitioning in the male set resulted in five subgroups. Two of them were related to diseased patients: 1) diabetes and 2) hypogonadism patients. Analysis of the female set suggested that it was more homogeneous than the male dataset. No evidence of pathological patient subgroups was found. In the study we showed that outlier detection with MD and rMD allows not only to identify outliers, but can also assess the heterogeneity of a dataset. The case study proved that our procedure is well suited for identification and visualization of biologically meaningful patient subgroups.

These data sets were originally created for the following publications:

M. E. Houle, H.-P. Kriegel, P. Kröger, E. Schubert, A. Zimek
Can Shared-Neighbor Distances Defeat the Curse of Dimensionality?
In Proceedings of the 22nd International Conference on Scientific and Statistical Database Management (SSDBM), Heidelberg, Germany, 2010.

H.-P. Kriegel, E. Schubert, A. Zimek
Evaluation of Multiple Clustering Solutions
In 2nd MultiClust Workshop: Discovering, Summarizing and Using Multiple Clusterings Held in Conjunction with ECML PKDD 2011, Athens, Greece, 2011.

The outlier data set versions were introduced in:

E. Schubert, R. Wojdanowski, A. Zimek, H.-P. Kriegel
On Evaluation of Outlier Rankings and Outlier Scores
In Proceedings of the 12th SIAM International Conference on Data Mining (SDM), Anaheim, CA, 2012.

They are derived from the original image data available at https://aloi.science.uva.nl/

The image acquisition process is documented in the original ALOI work: J. M. Geusebroek, G. J. Burghouts, and A. W. M. Smeulders, The Amsterdam library of object images, Int. J. Comput. Vision, 61(1), 103-112, January, 2005

Additional information is available at: https://elki-project.github.io/datasets/multi_view

The following views are currently available:

Feature type	Description	Files
Object number	Sparse 1000 dimensional vectors that give the true object assignment	objs.arff.gz
RGB color histograms	Standard RGB color histograms (uniform binning)	aloi-8d.csv.gz aloi-27d.csv.gz aloi-64d.csv.gz aloi-125d.csv.gz aloi-216d.csv.gz aloi-343d.csv.gz aloi-512d.csv.gz aloi-729d.csv.gz aloi-1000d.csv.gz
HSV color histograms	Standard HSV/HSB color histograms in various binnings	aloi-hsb-2x2x2.csv.gz aloi-hsb-3x3x3.csv.gz aloi-hsb-4x4x4.csv.gz aloi-hsb-5x5x5.csv.gz aloi-hsb-6x6x6.csv.gz aloi-hsb-7x7x7.csv.gz aloi-hsb-7x2x2.csv.gz aloi-hsb-7x3x3.csv.gz aloi-hsb-14x3x3.csv.gz aloi-hsb-8x4x4.csv.gz aloi-hsb-9x5x5.csv.gz aloi-hsb-13x4x4.csv.gz aloi-hsb-14x5x5.csv.gz aloi-hsb-10x6x6.csv.gz aloi-hsb-14x6x6.csv.gz
Color similiarity	Average similarity to 77 reference colors (not histograms) 18 colors x 2 sat x 2 bri + 5 grey values (incl. white, black)	aloi-colorsim77.arff.gz (feature subsets are meaningful here, as these features are computed independently of each other)
Haralick features	First 13 Haralick features (radius 1 pixel)	aloi-haralick-1.csv.gz
Front to back	Vectors representing front face vs. back faces of individual objects	front.arff.gz
Basic light	Vectors indicating basic light situations	light.arff.gz
Manual annotations	Manually annotated object groups of semantically related objects such as cups	manual1.arff.gz

Outlier Detection Versions

Additionally, we generated a number of subsets for outlier detection:

Feature type	Description	Files
RGB Histograms	Downsampled to 100000 objects (553 outliers)	aloi-27d-100000-max10-tot553.csv.gz aloi-64d-100000-max10-tot553.csv.gz
	Downsampled to 75000 objects (717 outliers)	aloi-27d-75000-max4-tot717.csv.gz aloi-64d-75000-max4-tot717.csv.gz
	Downsampled to 50000 objects (1508 outliers)	aloi-27d-50000-max5-tot1508.csv.gz aloi-64d-50000-max5-tot1508.csv.gz

Boston Housing Dataset

The Boston Housing dataset is a well-known dataset in the field of predictive modeling and statistics. It contains information collected by the U.S. Census Service concerning housing in the area of Boston Mass.

Dataset Overview

• Number of Instances: 506
• Number of Attributes: 14 (including the target variable)

Attributes

The dataset includes the following features:

1. CRIM - Per capita crime rate by town.
2. ZN - Proportion of residential land zoned for lots over 25,000 sq. ft.
3. INDUS - Proportion of non-retail business acres per town.
4. CHAS - Charles River dummy variable (1 if tract bounds river; 0 otherwise).
5. NOX - Nitric oxides concentration (parts per 10 million).
6. RM - Average number of rooms per dwelling.
7. AGE - Proportion of owner-occupied units built prior to 1940.
8. DIS - Weighted distances to five Boston employment centers.
9. RAD - Index of accessibility to radial highways.
10. TAX - Full-value property tax rate per $10,000.
11. PTRATIO - Pupil-teacher ratio by town.
12. B - ( B ) stands for ( 1000(Bk - 0.63)^2 ) where ( Bk ) is the proportion of Black residents by town.
13. LSTAT - Percentage of lower status of the population.
14. MEDV - Median value of owner-occupied homes in $1000s (target variable).

Use Cases

This dataset can be used for:

• Regression Analysis: To predict the value of homes based on the features provided.
• Exploratory Data Analysis: To analyze the relationships between different variables.
• Machine Learning: As a benchmark dataset for testing regression models.

Citation

Details about the dataset and its original source can be found in the following reference:

• Harrison, D. and Rubinfeld, D. L. (1978). "Hedonic housing prices and the demand for clean air." J. Environ. Economics and Management, 5, 81-102.