Collecting and analyzing numerical data or making numerical summaries of data.

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0
votes
0answers
14 views

Distance to river square grids [on hold]

I have a square grid 5X5 km and I want to create a field containing the distance from a river shapefile of each cell. Moreover I would like to have some tips about an inverse correlation between ...
12
votes
4answers
627 views

How is margin of error reported on a map?

When reporting estimates you should always include the margin of error. There are conventional ways of reporting margin of error in a table, text or graph. But, how do you report margin of error for ...
2
votes
0answers
26 views

Issue with basic statistics function on certain attributes [on hold]

I am trying to use the basic statistics function in QGIS on an attribute in a vector shapefile but it reaches 6% and then gets stuck and does not load anymore. It works fine on other layers/other ...
2
votes
1answer
13 views

Quartiles from Raster Layer band

I'm building a plugin from QGIS, and I need to extract the values from the quartiles from a band in a raster layer. Does anyone knows how it is done?
1
vote
1answer
186 views

How I can sum 360 raster files in a folder with the Arcgis raster calculator?

In a folder I have 360 precipitation raster files and I want to sum them all to the raster calculator
1
vote
1answer
173 views

Accessing bands in .pix (PCIDSK) file in python/arcpy

I am trying to perform zonal statistics on a single band from a multi-band raster in .pix format. I have things working great with a tiff file. I am able to access the bands using this code: desc = ...
2
votes
1answer
226 views

Extracting LiDAR metrics with TerraScan

I want to extract from a las file statistics such as height percentiles (percentile 95, for example) among others. I can do it with Fusion (using Cloudmetrics and Gridmetrics tools), but I would like ...
2
votes
1answer
31 views

Average Nearest Neighbor does not have all the options

I have a point feature class that I used the Average Nearest Neighbor from the ArcGIS software to calculate the pattern. ArcGIS produces output chart that says whether the data is dispersed, random ...
1
vote
1answer
18 views

Average Nearest Neighbor tool extreme restuls for different area?

I'm using the "Average Nearest Neighbor" tool in ArcGIS 10.3 to calculate whether my point feature class is clustered, random or dispersed. One of the parameters is area. I tried putting different ...
0
votes
1answer
19 views

How to work with Spatial Autocorrelation (Morans I) on equal weighted point

I have a point feature class. All points are the same, it's not weighted. I want to use Spatial Autocorrelation (Morans I) tool but it only takes a field for weight. I tried fooling it by adding a ...
0
votes
1answer
18 views

Graphic output for Ripleys K function

I am using ArcGIS to calculate Ripleys K function using the "Multi-Distance Spatial Cluster Analysis (Ripleys K Function)" tool on a point feature class. I can see a table output but want a graphical ...
1
vote
1answer
32 views

Creating quadrats in ArcGIS

Is there a tool / toolbox in ArcGIS to create quadrats on a population? I have a point feature classes with 1 billion points (divided to 10 almost equal feature classes) that I want to take samples ...
1
vote
0answers
9 views

How to apply Edge Correction in ArcGIS Average Nearest Neighbor

I am using ArcGIS 10.3 with the tool Average Nearest Neighbor to describe the data. I want to avoid mistakes caused by Edge Effect. In the Ripleys K Function tool there is an option to control that ...
0
votes
1answer
68 views

What is (if there's any) difference between MAUP and Edge Effect

I heard both the term MAUP and Edge Correction in association with Spatial Statistics, zoning/quadrats, demographics etc. Is there a difference between the two? What is the difference then?
3
votes
3answers
27 views

How do I calculate average in my field calculator within specified limit?

I would like to calculate the average, max and min of each trips that I have. Each trips are also predefined (e.g. Trip 1, Trip 2) in the attribute table. (As below). I have more than 2000 trips. ...
2
votes
1answer
31 views

Using zonal_stats with python in QGIS to calculate statistics for each image

I work with Python in QGIS, I want to calculate statistics for each image that I have with a specify shapefile and save result after, I tried to do like this: from rasterstats import zonal_stats ...
12
votes
6answers
5k views

Get Raster Values from a Polygon Overlay in Opensource GIS Solutions

I have two layers. A polygon-shape-layer with many tiles and a raster-layer containing CORINE 2006 land cover with many categories in a colourmap. I want to obtain for each polygon in the shapelayer a ...
3
votes
1answer
35 views

Calculating summary statistics and access resulting value in table using ArcPy?

With arcpy, I want to calculate the mean value of a specific field in a shapefile and print the resulting value for the user. I use the Summary Statistics tool and it works, but the resulting value ...
3
votes
2answers
121 views

Retrieving LiDAR metrics from relative vertical layers of point cloud

I need to obtain the proportion of all returns within 5 equally spaced height bins between the cutoff (1 meter) and the maximum height value. I need to get this proportion of all returns for 1000 ...
3
votes
1answer
52 views

Table of statistics of rasters input in QGIS

I work with QGIS GDAL,I have many raster image 'geotiff' with one band for many dates, I want to create a table that contains statistics for all rasters that I have. I tried the algorithm 'raster ...
0
votes
1answer
39 views

Correlating raster layers

I am trying to correlate contaminant data with other variables. For instance I want to see if high values of contamination coincide with topographic lows in my elevation raster (DEM). All the layers ...
0
votes
1answer
855 views

How to calculate median value of polygon from points in ArcGIS?

I have a point layer coming from LIDAR data containing x,y,z and intensity values. On the other hand I have a layer containing several polygons. All the points are inside the polygons. I need to ...
18
votes
3answers
639 views

Major bug in ArcGIS Zonal statistics?

Update: The bug has been fixed in the ArcGIS 10.4 release I am using ArcGIS 10.2.2 to determine zonal statistics for a number of zones. If there is any NoData in the value raster, I want the zone ...
5
votes
0answers
239 views

Zonal Histogram Output Problems - No values associated with the habitat type [closed]

I have a outline of some islands (shapefile or raster) and GAP landcover data (raster). I am trying to use Zonal Histogram to create a file with a histogram of the habitat types in each island. Each ...
0
votes
1answer
45 views

Identify the top 10% of raster cells

I have a raster with different risk values for a hazard. How can I identify the top x% (eg. 10%) of the raster cells with the highest values within ArcGIS?
1
vote
1answer
30 views

Replace Statistics_analysis with SearchCursor?

I'm using ArcGIS 10.3, 64bit with an advanced license. I have the following code, that runs just fine. It goes through a table that contains a large number of entries with zip-codes and population ...
0
votes
0answers
17 views

Normal distribution of residuals in regression analysis

I conduct regression analysis in ArcGIS to identify and model different independent variables that correlate with a dependent variable. First, I try to find a valid global Regression model using the ...
7
votes
2answers
111 views

How to automatically sum up values within buffers?

I want to establish the population figures within multi-ring buffers around certain site. I have set up the buffers and am running a select by location query on each concentric ring. Once the ...
1
vote
0answers
36 views

How to perform statistical test for two sets of points?

(I have asked this question originally on Cross Validated; however, no good answer and someone suggested me to ask the question here). We know that we can perform statistical test (e.g., t-test) for ...
9
votes
5answers
12k views

How to calculate raster statistics for polygons?

how can I calculate sums, averages etc of raster-points (multi-band) per polygon of a vector-layer. I was told that this is called "zonal statistics". I tried that with QGIS first. There is a way to ...
1
vote
1answer
255 views

How to calculate raster statistics for each band in qgis

i need to calculate raster statistics for RGBN (4 channels, multiband image) rasters in QGIS. In Arcgis if you use "calculate statistics" in Arcatalog, statistics are calculated for every image band. ...
0
votes
2answers
42 views

More information from Summary statistics tool in ArcGIS

I try to find the MAX value for every distinct element in a dataset (I done this using MAX in summary statistics) but I also want to have the id of the element corresponding of that MAX in my output ...
1
vote
1answer
41 views

Calculate the frequency of classes of neighbouring raster cells

I'm struggling with a problem when working with a raster dataset of biotope types: For each cell I would like to find out the frequency of classes in the adjacent cells, e.g. from the 8 neighbouring ...
2
votes
1answer
38 views

Performing Statistics operation on field in Attribute table?

I am working with the Shapefile consisting set of points. One of its field (let's call it X) contains numeric data, ranging from 0 to 1. In order to find out the average value of field X, I opened ...
6
votes
1answer
2k views

ArcGIS median value from layer?

I've been hunting around ArcGIS 9.3 and having no success at finding a tool/function that can give me the median (not the mean/avg) tabular value of a spatial database. For example, if I have a data ...
2
votes
1answer
67 views

Extracting NDVI using QGIS from multiple images to Excel?

I created 25 images in QGIS. Each image has different information about the NDVI of the area. How can I extract mean, max, and min information about the NDVI from each image and put it in Excel?
1
vote
1answer
40 views

extracting statistics from a raster within the extent of a polygon

I have a polygon representing the extent of a study area. This polygon is overlaid to a raster representing the quality of land, which is classified into 5 classes (from bad [1] to good [5]). I would ...
4
votes
3answers
3k views

How to count occurrences of one field grouped by values of another?

Is there a way of calculating the number of unique text strings in a field in ArcGIS 10.1? I have a number of repeated strings in this field, but would like to calculate the number of unique strings ...
1
vote
1answer
749 views

Deriving Z-score values for given field using ArcGIS for Desktop?

I have a shapefile with an attribute field with a range of numerical values. How do I derive z-score values for this field using ArcGIS for Desktop?
2
votes
0answers
36 views

How can I statistically compare the surface slope of 2 different areas?

I could use the statistical tests like t-test and ANOVA, however I am afraid those test will easily show significant differences if I use the slope values of all cells from each area.
4
votes
2answers
105 views

how to get max and min from a raster using arcpy?

I have a land surface temperature raster file and I want the max and min of it. minLSTresult = arcpy.GetRasterProperties_management(raster_result, "MINIMUM") minLST = minLSTresult.getOutput(0) ...
1
vote
2answers
79 views

Error Trying to Run R Summary Statistics in QGIS 2.12.1

When I try to run the R script "Summary statistics" in QGIS 2.12.1 on a Windows 7/64 bit machine, I get the error message "error in if (!file.info(DSN)$isdir) DSN missing value where TRUE/FALSE ...
5
votes
1answer
4k views

Recording frequency of names in the attribute table?

I have a question with ArcGIS 9.2. In an attribute table the column [name] includes the name of every place in this layer. Next to that (in columns [numbers]) there should be recorded how often a ...
4
votes
1answer
92 views

Finding Median, Max and Min values from Raster Layers in QGIS

I currently have 10 years worth of January raster datasets (working on just one month at the moment) of cloud fraction cover from MODIS, and am trying to create new 3 separate rasters which will give ...
0
votes
1answer
71 views

Calculate percentages with field calculator in arcgis?

I am trying to calculate the percentage of each the area of each polygon in the selected area. I tried using ( math.fsum(!shape.area!) / !PolygonArea! )*100 and other codes but I cannot make it work. ...
0
votes
1answer
33 views

Cell Statistics failing to read rasters in list

Heyo. I'm trying to get the rasters from a list (about 32 rasters) and then sum them up with CellStatistics in arcpy. I'm using Python 2.7.8 and ArcGIS 10.3.1 I got it to work the first time around ...
2
votes
1answer
58 views

Resampling gives higher MEAN when using zonal statistics

I am using ArcGIS 10.1 for Desktop. I have a value raster and a polygon feature in GCS coordinates. My raster resolution is 0.5 decimal degrees which is much larger than the size of my polygons. My ...
9
votes
1answer
283 views

Calculating spatial correlation between features from two separate layers in QGIS

I am trying to determine whether the presence of large numbers of active duty military troops in an area is spatially correlated with higher/lower levels of violent crime. That is, are the areas ...
8
votes
3answers
268 views

spatial and spatiotemporal analyses

I have a dataset that consists of 247 mosquito traps placed in fixed positions and sampled weekly for 23 weeks. I also have dengue disease incidence data (indexed to home address) during the same time ...
0
votes
0answers
25 views

Extremely high z-values for Moran's I

I made the following in advance: I aggregated population data to 100*100m Grids. Afterwards I wanted to find out, weather there is autocorrelation in the data or not. For this I applied the Moran's I ...