USING UNIVARIATE AND MULTIVARIATE METHODS TO DETECT OUTLIERS IN SEDIMENT FINGERPRINTING METHOD, CASE STUDY: TANGE BOSTANAK WATERSHED

Q: How can I download an article?

To download an article from SID, first log in to the site, search for the article title, and click on the 'Download Article' option.

Q: How can I download an ISI article?

To download an ISI article on SID, enter the keyword or article title in the search bar, view the relevant results, click on the desired article, and select the 'Download Article' option.

Q: How can I access the SID database?

To access the SID database, visit SID.ir, create an account, and log in to access scientific resources.

Q: Is downloading articles from SID free?

Some articles on SID are available for free, while others require payment. Details are specified on the article's page.

NOHEGAR AHMAD; KAZEMI MOHAMMAD; AHMADI SEYED JAVAD; GHOLAMI HAMID

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

Journal Paper

Paper Information

Journal: WATERSHED ENGINEERING AND MANAGEMENT Year:2018 | Volume:9 | Issue:4 Page(s): 398-412

Download Full-Text

Persian Verion

View:

1,016

Download:

Cites:

Information Journal Paper

Title

USING UNIVARIATE AND MULTIVARIATE METHODS TO DETECT OUTLIERS IN SEDIMENT FINGERPRINTING METHOD, CASE STUDY: TANGE BOSTANAK WATERSHED

Author(s)

NOHEGAR AHMAD | KAZEMI MOHAMMAD | AHMADI SEYED JAVAD | GHOLAMI HAMID | Issue Writer Certificate

Keywords

GRUBBS' TESTQ1

MAHALANOBIS DISTANCEQ1

PCAQ2

SEDIMENT FINGERPRINTINGQ1

TRACERSQ1

Abstract

Efficiency of SEDIMENT FINGERPRINTING by using TRACERS as a successful method to determine the sources of sediment has been proved. Selection of the suite subset of TRACERS, capable of discriminating sediment sources, is the first and the most important step in the SEDIMENT FINGERPRINTING method. The presence of outliers affects the selection of the suite subset and possibly prevents picking the important TRACERS and reducing the accuracy of classification. Therefore, the outliers must be detected in order to be corrected or omitted, if enough evidences were present. The present study aims to detect outliers in the subset of TRACERS, to identify the best combination. For detecting outliers, We used univariate methods such as Grubbs test, Gauss test, Dioxin test, box plot, the Median ± 3MAD, the mean ± 3standard deviation and also multivariate methods such as squared MAHALANOBIS DISTANCE, separate box plots of squared MAHALANOBIS DISTANCE for each of sediment sources, principal component analysis and plot of the squared MAHALANOBIS DISTANCEs against the quantiles of the chi-square distribution. we consider an observation as the outlier that at least half of these methods have detected it as an outlier. The results showed that Median ± 3MAD method introduced a larger number of data as outliers Methods of multivariate outlier detection has low agreement with each other. Univariate methods to identify outliers show higher agreement with each other. To use univariate analysis techniques to detect outliers namely Median ± 3MAD, box plot, and Dioxin one can recommended to test their sensitivity. The results also showed that the maximum consensus for univariate analysis techniques is four samples (observations) and for multivariate methods is two samples (observations). In general, there is no observation that is identified as an outlier by half of the used methods.

Cites

No record.

References

No record.

Cite

APA: Copy

NOHEGAR, AHMAD, KAZEMI, MOHAMMAD, AHMADI, SEYED JAVAD, & GHOLAMI, HAMID. (2018). USING UNIVARIATE AND MULTIVARIATE METHODS TO DETECT OUTLIERS IN SEDIMENT FINGERPRINTING METHOD, CASE STUDY: TANGE BOSTANAK WATERSHED. WATERSHED ENGINEERING AND MANAGEMENT, 9(4 ), 398-412. SID. https://sid.ir/paper/234568/en

Vancouver: Copy

NOHEGAR AHMAD, KAZEMI MOHAMMAD, AHMADI SEYED JAVAD, GHOLAMI HAMID. USING UNIVARIATE AND MULTIVARIATE METHODS TO DETECT OUTLIERS IN SEDIMENT FINGERPRINTING METHOD, CASE STUDY: TANGE BOSTANAK WATERSHED. WATERSHED ENGINEERING AND MANAGEMENT[Internet]. 2018;9(4 ):398-412. Available from: https://sid.ir/paper/234568/en

IEEE: Copy

AHMAD NOHEGAR, MOHAMMAD KAZEMI, SEYED JAVAD AHMADI, and HAMID GHOLAMI, “USING UNIVARIATE AND MULTIVARIATE METHODS TO DETECT OUTLIERS IN SEDIMENT FINGERPRINTING METHOD, CASE STUDY: TANGE BOSTANAK WATERSHED,” WATERSHED ENGINEERING AND MANAGEMENT, vol. 9, no. 4 , pp. 398–412, 2018, [Online]. Available: https://sid.ir/paper/234568/en

Related Journal Papers