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

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2answers
60 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 ...
3
votes
1answer
66 views

Statistical Analysis of Shapefile Proximity within Raster Image - ArcMap10.1

I have a raster image that has been reclassified into 15 equally incremented values/levels. This raster represents "sinkhole risk" in a certain county. So level 1 is the lowest risk region and level ...
0
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1answer
54 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
0
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1answer
58 views

Creating quintiles in QGIS when the number of observations per row is variable

I have a list of 100s of schools (1 per row), and a variable column with the total students in each school. The number of total students in each school varies widely. I want to split the list of ...
3
votes
0answers
120 views

Why are my raster mean and standard deviation -1?

I have a set of about 25 rasters whose descriptive statistics I have been examining. The data in the rasters were calculated in Python and the rasters were created using Python-GDAL. In all but one ...
2
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0answers
89 views

How do I statistically compare positions from two track datasets?

I have two datasets with positions that I need to compare. One would be the "observed" positions (someone took the GPS positions manually) and the other one was calculated using a software. To use ...
2
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0answers
111 views

Bivariate Mapping (running a single variable regression and mapping r-squared value)

I am hoping to produce a bivariate map displaying the correlation between two variables (specifically percent SNAP participation by county against several social variables). I would like to produce ...
2
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0answers
29 views

Is there a way to find the closest anticorrelated polygon or automate what is learned in the semivariogram?

I am trying to do spatial autocorrelation of sorts based on a layer of polygons of mean rainfall data. I want to see how rainfall deviates from a certain point on the landscape. Essentially, I want to ...
2
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0answers
72 views

How to join two fields after calculating?

I have been working with two layers and I am trying to join them and turn them into a raster data. The first layer is a watershed layer which I have assigned each shed a location from the center point ...
2
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0answers
308 views

On using R data with ArcPy to make histogram in ArcMap

I am writing a tool in python which passes parameters to a R script, which in turn creates a DBF file. I read this DBF and want to make a histogram out of the data inside ArcMap as one of the results ...
2
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0answers
330 views

How do I create a leader line for a label in my bar graph in ArcMap?

I am displaying a bar graph of various tornado watches and warnings along with the actual tornado touchdowns themselves. Since the tornado touchdowns are such a small number compared to the large ...
1
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0answers
22 views

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

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 ...
1
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0answers
34 views

Web mapping API popularity

Are there any online statistics for the popularity/usage of web mapping APIs? A diagram would be sufficient, if it can be published in a paper. I have only found one source: ...
1
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0answers
30 views

Plotting N-S and E-W Profile of Land Surface Temperature (LST) Across Land Use types in ArcGIS for Desktop?

I am working on my final year thesis and I need to plot the seasonal North-South and East-West profile of land surface temperature (LST) across various land use types. I have been able to extract ...
1
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0answers
62 views

Statistically compare two density maps?

I (will) have a modelled distribution and an observed distribution of animals. If I were to interpolate these position datasets to reflect some density distribution (perhaps using a kriging ...
1
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0answers
45 views

How to export raster into ascii without losing the statistics?

I had a problem in Mike Urban with a difference between a DEM (Digital Elevation Model) and a 2D overflood model and the support group requested me to remove the difference because the problems were ...
1
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0answers
86 views

Mann-Whitney U test for rasters

I'm doing a Mann-Whitney U test to compare two very large samples (sample size 1 = 13250; samlple size 2 = 38871) originating from a shapefile with 52121 features. I know t-tests are not recommended ...
1
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0answers
101 views

Reshape Matrix and perform Zonal Statistics in Matlab

I have 2 grids: 1) n by m - at 100m 2) n*10 by m *10 - at 10m. These grids cover the same area. I have to perform zonal statistics at scale of grid no.2. Cell value of grid no.1 is cumulative for ...
1
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0answers
402 views

QGis Grid statistics for polygons error - Module caused access violation!

I'm trying to calculate statistics for a raster layer using an overlaying polygon layer, I'm using SAGA "Grid Statistics for polygons" function, but it returns an error, sadly.. So in the sextante log ...
0
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0answers
27 views

Finding Cooks Distance on ArcGIS

is there a way to find Cooks distance on ArcGis or do I have to use SPSS?
0
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0answers
27 views

Metrics of change between vector datasets

I have an old and a new set of parcel data which I'm looking to compare. I'm looking to compare changes in individual parcel geometries, so boundary/corner adjustment. Currently each parcel we have ...
0
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0answers
32 views

Zonal statistics vs. random points?

Using ArcGIS 10.1 for Desktop, I wish to model the relation between soil productivity (SP) and a number of independent variables such as, e.g., terrain elevation and slope. For this purpose, I am ...
0
votes
0answers
112 views

pivot table output

In an attempt to summarise landclasses, the columns of my pivot table output are a bit mixed up with the field info regarding the three input fields that I've selected. As shown in snapshot 3 the ...
0
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0answers
39 views

Performing Mutiple Correspondence Analysis (MCA) using R?

I want to apply MCA (multiple correspondence analysis) to a data table containing regions as individuals, and INFESTED AREA as variable and degree infested also and the type of trees infested , and I ...
0
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0answers
52 views

Sextante and qgis for hotspot analysis

I want to analyze time series data for hotspot analyis. May i know whether sextante and qgis are able to generate any spatial statistics similar to Getis-O-ord in ARCGIS.Or R is required for hotspot ...
0
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0answers
50 views

Why does it take so long to run zonal statistics?

QGIS 2.0 Windows 7 I have pulled agricultural data from NASS CDL in tiff format. I want to track where a certain crop has grown over the years. My intention was to use a county shapefile overlaid ...
0
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0answers
29 views

Cell Statistics in QGIS

Cell Statistics in ArcGIS will calculate the mean (or statistic of choice) among multiple rasters on a cell-by-call basis. Can QGIS do this? If so, how?
0
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0answers
114 views

Calculate ANOVA using GIS

It's possible to calculate a statistic like ANOVA using GIS. I'm using ArcGis, but there's any GIS software to calculate it? Thanks,
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0answers
48 views

Zonal statistics returns wrong values in QGIS

I used zonal statistics for a simple task: to transmit raster pixel values to vectormap which contains squares as big as the pixel size is. The problem is that the values of the outcome are not ...
0
votes
0answers
38 views

How to extract high frequencies from a point shapefile?

I need to get the average of the 3 highest frequencies in a table and append it to a shape file i already have hope you can help me