Questions tagged [outlier]

In statistics, an outlier is an observation point that is distant from other observations.

Filter by
Sorted by
Tagged with
11
votes
2answers
13k views

What algorithm should I use to remove outliers in trace data?

I have GPX traces and want to remove outlying observations. There are some route points that are impossible because it would require acceleration that the vehicle can not achieve. Are there good ...
10
votes
8answers
4k views

Editing LiDAR point cloud to remove noise/outliers present below and above ground?

I have "dirty" LiDAR data containing first and last returns and also inevitably errors under and over the surface level. (screenshot) I have SAGA, QGIS, ESRI and FME at hand, but no real method. What ...
9
votes
6answers
6k views

Detecting and fixing outliers in a GPS trajectory

I need to find an algorithm or method that can detect outlier latitude longitude points in a trajectory during post-processing, which can then be fixed (brought back into the trajectory's path based ...
6
votes
3answers
2k views

Finding outliers with wrong Z values in LIDAR data

I have more than 2000 XYZ (only ground points) .txt files and I have to do Quality Control (QC). Let's say I have file, which I converted to multipoint (or even singlepart feature). I have mean Z ...
6
votes
1answer
5k views

How to exclude outliers from raster using ArcGIS for Desktop?

I calculated terrain curvature from a DEM. The DEM I use is interpolated from point elevation data. Generally, the DEM seems to be good, but some artifacts from interpolation exist. Those artifacts ...
5
votes
2answers
623 views

Cleaning LiDAR points that classification algorithm misses?

There are numerous methods for classifying ground and not-ground points from raw LAS point clouds. They all do a great job, depending on local circumstances, but inevitably even when algorithm and ...
4
votes
1answer
895 views

Deleting anomalous points in *.lasd using ArcGIS for Desktop?

I am using ArcGIS 10.3.1 for Desktop. I have a raw .las file that I have brought into an ArcGIS .lasd file format. The raw data has several anomalous points; i.e. the maximum elevation for any point ...
3
votes
1answer
121 views

Mapping/visualising data with Long Tail?

I work with a dataset that gathers stats from all across a city. Each datapoint is of interest and worth visualising to our users, but there are a few parts of the city that significantly deviate from ...
2
votes
1answer
400 views

QGIS: How to exclude outliers from the legend classfication using an expression

I am trying to make an equal interval legend using a rate of burglaries per 1000 habitants using a combination of a column with the counts of burglaries and a column of total population using census ...
2
votes
0answers
251 views

Is median center more influenced than mean center by value outlier in ArcMap?

I noticed something strange or seemingly paradoxical in ArcMap 10.2.2. The median center is less influenced by spatial outliers than mean center, this is a fact. The thing is, I created 6 dispersed ...
1
vote
1answer
148 views

Converting DEM to use with Locate Outliers tool in ArcGIS?

I have a DEM and I want to analyse it using the Locate Outliers tool in ArcMap; however the tool only supports Terrain or LAS input files. How to convert the raster DEM to a format that Locate ...
1
vote
1answer
111 views

Show groups of coordinates on a map, to visually find coordinates that belong to the wrong group

I have a (very) long list of casinos. Each casino has: latitude longitude boss (a single boss runs from 1 to 50 casinos) Sample: 40.642 -73.997 Freddy Queens 40.680 -73.985 Freddy Queens 40.697 -73....
0
votes
1answer
237 views

Locating outliers in LAS Dataset with ArcGIS?

According to the statistics and symbology of my LASD I have outliers. See below: How can I locate them in ArcGIS 10.x and do further analysis with them? I cannot query the dataset or select point? So ...
-1
votes
1answer
97 views

Running cluster and outlier analysis gives ERROR 999998?

I am attempting to run Cluster and Outlier Analysis on a Shapefile Feature Class. The geometry type is a line feature class. I am receiving the following error when attempting to use this tool: ...