The ListPOR program (List Parser for Outlier Removal) can be used to read a file containing columns of grouped values and remove outlier values using Grubb’s test.


The ListPOR program can be used to read a file containing columns of grouped values and remove outlier values using Grubb’s test. Typically, the first column of the input file will contain key information (text or numbers) on which to group the data. The second column will contain the values to examine for outliers, examining the data by groups. If additional columns are present, they will be written to the output file along with the key and value columns. Alternatively, if you provide a file with only one column of data, then all of the values will be examined en masse and the outliers removed. A simple graphical user interface (GUI) is provided to allow the user to select the input file and set the processing options.



All publications that utilize this software should provide appropriate acknowledgement to PNNL and the ListPOR GitHub repository. However, if the software is extended or modified, then any subsequent publications should include a more extensive statement, as shown in the Readme file for the given application or on the website that more fully describes the application.


These programs are primarily designed to run on Windows machines. Please use them at your own risk. This material was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor the United States Department of Energy, nor Battelle, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness or any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights.

Portions of this research were supported by the NIH National Center for Research Resources (Grant RR018522), the W.R. Wiley Environmental Molecular Science Laboratory (a national scientific user facility sponsored by the U.S. Department of Energy’s Office of Biological and Environmental Research and located at PNNL), and the National Institute of Allergy and Infectious Diseases (NIH/DHHS through interagency agreement Y1-AI-4894-01). PNNL is operated by Battelle Memorial Institute for the U.S. Department of Energy under contract DE-AC05-76RL0 1830.

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