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

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1
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2answers
215 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
3
votes
2answers
68 views

ArcGIS: table statistics range, method?

I have the following table with distance values (NEAR_DIST) after using the "Near" tool in ArcGIS: I am looking for a method of getting the following statistical information/statement, for example: ...
3
votes
1answer
41 views

An equivalent for field statistics for records

I know how to obtain various statistics for a field, or "column", in an attribute table in ArcGIS. Is there any way to obtain a Mode figure for records, or the "rows" in a table? For instance, an ...
1
vote
1answer
186 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 = ...
0
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0answers
15 views

What units are associated with these raster bands?

The picture is a scatterplot of roughly 400 pixel values from 4 different raster bands. Im curious what the units are? They do not correspond with the sensor's band values. Sensor is WV-II. 1 - Red ...
0
votes
1answer
33 views

Finding field with maximum value and field name using ArcPy cursor?

I was wondering if an equivalent of summary statistics exists for finding such statistics across fields rather than records in a table. For example, of several fields, I wanted to find which one has ...
0
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0answers
57 views

How to analysis the spatial distribution similarity?

There are three different data source aiming at atmospheric chemistry research: Simulated concentration of ground level air pollutant Satellite retrieved concentration for the same area. ...
2
votes
1answer
246 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 ...
1
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0answers
34 views

Summary statistics from feature iterator and select by location - missing selected feature name. Arcmap 10.2

I'm trying to calculate summary statistics for a subset of a point feature, based on selecting by location. I'm using a feature selection iterator to get statistics for each polygon feature in the '...
3
votes
1answer
42 views

Concerning “Error when using r.series in a python script”

Based on the "Error when using r.series in a python script" discussion (Error when using r.series in a python script) and based upon the solution given by Joseph I tried to make the same but by using ...
1
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0answers
34 views

Per-pixel Descriptive Statistics through multiple Raster layers

I'm looking for computing different descriptive statistics through a set of raster layers. I need to make it with a python script capable of running into a standalone tool within the QGIS. To do so ...
2
votes
1answer
375 views

Combining and displaying demographic data?

I am currently undertaking a demographic research project for my employer. We have the data on income, age, sex, language, transport etc and I have mapped most of it and created some thematics of said ...
1
vote
3answers
97 views

How to add a pie chart based on all (or some) features in a layer?

I have a vector layer in a QGIS project which has about 60 items with various attributes, including a check for if an item is complete. I am trying to get a pie chart showing the percentage of the ...
2
votes
1answer
31 views

Summarising an attribute from point layer in polygons with FME

I have a number of polygon feature sets and a point layer containing an attribute with population count. I want to summarise the population attribute for all points within each polygon feature set ...
2
votes
1answer
47 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 ...
0
votes
0answers
10 views

Minimum number of oservations in the dependent variable in regression

Is there a minimum number of observations that should be available when running regression (Ordinary Least Squares Regression in this case) for the dependent variable? I want to run several OLS ...
2
votes
1answer
197 views

Intersect shapefile with raster, then determine proportion of each raster value?

Using the arcpy module in Python, I want to find the proportion of each pixel value within the boundary of an overlaying polygon. (The polygon is in a shapefile.) For example, there are 10 possible ...
2
votes
0answers
31 views

Basic statistics function on certain attributes stops at 6% on certain layer in QGIS?

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 ...
12
votes
4answers
646 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 ...
3
votes
1answer
20 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?
2
votes
1answer
38 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
23 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
22 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
33 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
47 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
12 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
72 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
32 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. ...
13
votes
6answers
6k 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
53 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
147 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
56 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
44 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
892 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
777 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
263 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
55 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
19 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
129 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
56 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
367 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
45 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
59 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 ...
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
81 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
48 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
4k 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
863 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?