The degree of closeness of measurements of a quantity to that quantity's actual value

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7
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1answer
376 views

How to store Large Raster Images of Equipotential Surface Generation Using Monte Carlo Simulation?

I have a large (1GB+) raster that I am using as the base for the generation of an equipotential surface. This is to assess the accuracy of DEMs derived from another source. In situ observation is ...
1
vote
1answer
86 views

Elevation adjustment DSM using Ground control points

is there any possibility to improve the vertical accuracy of a given satelite DEM/DSM by using exact measured ground control points? And if so, which software is recommended?
1
vote
1answer
62 views

Checking the registration accuracy of already-orthorectified images

I acquired several Landsat 5-8 images corrected at Level 1T. I also have aerial ortophotos of the same area. From a visual assessment the co-registration between the images seems good, but I need to ...
1
vote
1answer
139 views

What sub-meter geolocation solutions exist and how can I integrate them into a web and mobile mapping workflow?

I am the manager of seven water systems. What I am trying to do is map out every meter and valve on to a map and then my workers can have the maps on their iPhones so when they have to go fix a water ...
0
votes
1answer
34 views

Creating a Grid For Raster When Measuring Land Cover In Accuracy Assessments

I am assessing the accuracy for the 2011 National Land Cover Map (NLCD). Each pixel for the NLCD measures 30m x 30m. For my reference data, I'm using two sources: 1) Google Earth (~20 m ...
0
votes
1answer
615 views

ENVI 5.2.1 How to do an Accuracy Assessment using test data from a shapefile

ENVI 5.2.1. From a .tiff image (4 bands) I created a Supervised Classification Maximum Likelihood .dat file. Now I want to perform an Accuracy Assessment using test data from a shapefile. I've tried ...
0
votes
1answer
158 views

Benefit of DGPS for relative accuracy and speed measurements for receivers close-by each other

Consider that we are interested only in the speed and relative position accuracy of GPS receivers (i.e. their absolute try position on earth is NOT important). These receivers are all in a 90m x 90m ...
3
votes
0answers
124 views

How to measure RTK accuracy of a moving vehicle?

I am currently working with tractors using a RTK enhanced automated steering system. One of the biggest problems is that even RTK can have a inaccuracy of 2cm. This can be too much for some possible ...
2
votes
0answers
3k views

Translating hdop, pdop and vdop to metric accuracy from given NMEA strings

How can I translate dilution of precision to a metric unit? For example: say I got 1.2 in hdop from NMEA sentence of my GPS receiver, in what should I multiply to get a metric accuracy? Just like the ...
1
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0answers
16 views

Is there a well-known way to compare the relative accuracy of 2 latitude/longitude results?

I have 2 geocoding results (in latitue and longitude) for a given address from different services. I'm interested in describing the results in relation to one another in terms of relative accuracy and ...
1
vote
0answers
25 views

Can typical Meets and Bounds (angles and distances) drawings be accurate in QGIS?

I’ve been working with parcel boundary shape files (.shp), standard satellite imagery, and Meets and Bounds (angles and distances) site maps / legal descriptions for a few weeks. Wondering if those ...
1
vote
0answers
446 views

Collector for ArcGIS PDOP and GPS collection configuration settings

My company just acquired a Geneq SXBlue II GPS receiver to pair with an iPad and the Collector for ArcGIS app. The functionality is awesome and loved by everyone, but since we have biologists on our ...
1
vote
0answers
98 views

How to select random objects in eCognition?

I classified a Landsat image in eCognition and now I want to select random objects so that I can compare their class to ground-truth data and perform the accuracy assessment. How can I do this in ...
0
votes
0answers
14 views

Proper Tool for Creating a 3x3 Window for Cluster Sampling in Accuracy Assessment?

I'm using a cluster sampling scheme for an accuracy assessment of the 2011 National Land Cover Dataset (spatial res of 30m). I'm using Google Earth Pro for my reference data spatial res of 15m). So ...
0
votes
0answers
30 views

Basemap (Matlibplot) not plotting GPS WGS84 coordinates accurately

I have a list of lat,lon coordinates from Flickr pictures taken in Sydney (see here) When I plot these points on google maps, the locations are correct. However when I use my Basemap the results are ...
0
votes
0answers
64 views

Using shapefiles as a reference for accuracy assessment in ecognition

I classified my project and got an esri shapefile with points in it. Those points are hand made samples with the right class assigned to them. Now I need to use those samples to check my own ...
0
votes
0answers
80 views

How to randomly generate 3 X 3 pixel window/grid size in ArcMap?

I have a raster image in ArcMap and I want to assess the accuracy of my raster image with a reference image. So, I need to randomly generate a bunch of (i.e 50) 3 X 3 pixel window/grid size from my ...
0
votes
0answers
237 views

ERDAS file not recognized as ERDAS Hierarchal File Architecture (EFHA)?

I am trying to do an accuracy assessment in Erdas using "user defined ground control points" (I collected the GPS points myselfin the field using a handheld GPS). However, when I load the thematic ...