The closeness of a repeated set of observations of the same quantity to one another.

learn more… | top users | synonyms

60
votes
3answers
33k views

How to measure the accuracy of latitude and longitude?

I am very new to GPS stuff. Suppose I have latitude and longitude as 19.0649070739746 and 73.1308670043945 respectively. So now both co-ordinates are 13 decimal places long. But sometimes, I also get ...
7
votes
1answer
388 views

Need to learn more about Precision and Accuracy

I am currently taking Introduction to Image Interpretation online and there is a section in it that talks about Precision and Accuracy. I wanted to know if someone out there has any good information ...
6
votes
1answer
145 views

What is the precision of SELECT DISTINCT on PostGIS geometry column?

I wonder what the precision of the SELECT DISTINCT operator is on a PostGIS geometry. On my system, the following query gives me a count of 5, which means that the inserted points are considered equal ...
5
votes
3answers
227 views

Precision vs Resolution in elevation data

Update: A good example of my confusion: on the Wikipedia page for "digital terrain model" one can find the following statement about a satellite in the "See Also" section: TanDEM-X: generation of ...
5
votes
2answers
452 views

Accuracy vs Precision GPS

I am doing some research on consumer grade GPS accuracy and precision. I took 5 readings for 20 known locations (100 readings). Am I correct in assuming that the standard deviation between the 5 ...
5
votes
2answers
3k views

Correct way to create a DEM from point data in csv files

I know this might seem a somewhat general question, but I have to start somewhere. I have a lot of csv files which contain point data containing height, aspect and slope measurements at a resolution ...
4
votes
1answer
188 views

Display XY Format to Shapefile (Scale)

Using ArcView 10.1 and using excel for Lat/Long conversion to a shapefile. The original Lat/Long has 7 numerical characters past the decimal point xx.1143717. When I convert this excel into a ...
2
votes
1answer
86 views

What is a reasonable time to get a gps fix with 10 meters precision?

I hope I'm asking this at the right part of Stack Exchange. Please bear with me if I'm wrong. I'm developing some gps based applications. The demands I have for precision are not very high, but I ...
2
votes
1answer
60 views

What are arc's guarantees on data precision, XYTolerance (i) when displaying (ii) in arcpy?

Interesting behaviour: Two line segments in a dataset have almost, but not quite, identical endpoints. The difference between them is less than the XYTolerance for the data set. Reading the ...
2
votes
0answers
118 views

Spatial Precision for Editing in Multiple GIS Clients

I have something I'd like to discuss, I'll try to explain it first, why it's important, and I'll explain how ArcGIS handles the issue, which I think is a good way to handle it. Finally I'd like to ...
1
vote
3answers
1k views

How to auto fill or delete sliver polygons without losing precision?

I am developing some boundaries in which precision holds the key value. Using ArcGIS 9.3 I am converting lines to polygons using the "feature to polygon" tool. The lines are accurate but I find ...
1
vote
0answers
30 views

Precision for an FGDB raster dataset?

I would like to know the precision for an ArcGIS raster stored within a file geodatabase (FGDBR format); I can't seem to find this information anywhere in their documentation (apologies if I have ...
0
votes
1answer
59 views

How can I change the precision in the attribute table?

I'm working with qgis, v. 2.0.1. I opened a csv-table (from an excel-file) and now the precision is very high but i don't need this. At the moment the values are for example 15.00000000000000, how ...
0
votes
0answers
30 views

A machine to measure latitude to 6 decimal places of a degree [duplicate]

I am doing a PhD research project to do with medieval and ancient archaeoastronomy which requires me to be able to measure latitudes up to an accuracy of 6 decimal places of a degree of latitude. ...