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

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2answers
54 views

Is it valid to adjust quantile buckets to “nice” numbers for better readability?

I'm making a map about terrorist attacks and fatalities in CartoDB. For data clustering I'm using quantiles. The calculated buckets are 16, 32, 50, 97, 700. Is it okay to adjust the quantiles to make ...
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2answers
67 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 ...
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1answer
82 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 ...
2
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1answer
73 views

Memory issues with zonal statistics

I have got a memory issue due to the use of the zonal statistics command into a loop. It seems that after using the ZS command QGIS stores some information in the RAM (cache memory?). It is not ...
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1answer
67 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 = ...
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1answer
85 views

Extract values from raster by using polygons

I am working with multiple raster files that cover all of united states. The file format of the rasters - GeoTIFF. I have around 100 geotiffs that I need to process. Then I have another shapefile with ...
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1answer
101 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
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1answer
91 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 ...
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0answers
110 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 ...
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59 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: ...
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0answers
31 views

Finding closest anticorrelated polygon or automate what is learned in 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 ...
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0answers
157 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 ...
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0answers
32 views

Zonal statistics error: 0-d arrays can't be indexed

How can I fix the error 0-d arrays can't be indexed? This message appears after the tentative to use the algorithm Qgis Zonal Statistics. Detail: the algorithm worked very well several times and then ...
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0answers
122 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
172 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
74 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 ...
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0answers
362 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 ...
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0answers
414 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 ...
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0answers
23 views

Invalid drop item: Calculate statistics

I have a number of rasters that I need to calculate histograms for. These are continuous rasters from 0 to 294.208 - many decimal places. I need to be able to classify the histogram down to at least ...
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0answers
19 views

Some output cells show up as noData in ArcMap Block Statistics?

I am using ArcMap 10.2.2, and I need to aggregate categorical data from 30m up to 90m and 900m resolution for species distribution modeling. The algorithms available in resample (nearest neighbor, ...
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0answers
74 views

Road traffic database sample?

I would like to do some experiments on a traffic forecasting neural network and I need some real traffic data to run the network. My question is where can I download some real traffic statistics data ...
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0answers
40 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 ...
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0answers
93 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 ...
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0answers
70 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 ...
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0answers
111 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 ...
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0answers
141 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 ...
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480 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 ...
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8 views

Different results of lagsarlm in R and GeoDa spatial lag model with identical weight matrix?

I ran a spatial lag regression model in R using spdep. Due to cross-validation of my results and data-size, I ran the same model in GeoDa but the resulting indices didn't match. My data(slot): ...
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35 views

Zonal Statistics as Table having problems with Mosaic Dataset

I have a mosaic dataset of forest cover around the globe for the year 2000 (each cell's number contains the percent of forest cover in that area). I have randomly selected a large number of points ...
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44 views

Overlay polygons on raster in different projections

I'm overlaying polygons on a raster to get the average value inside the polygon (using SAGA->Shapes-Grid->Add grid values to shapes in the QGIS Processing Toolbox), using a geographic and a ...
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0answers
40 views

k-fold cross validation in ArcMap?

k-fold cross validation in ArcMap? I observed some point I want instead of one point out several points for Cross validation I use, but I do not know how to do in ArcMap.
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28 views

Finding Cooks Distance on ArcGIS

is there a way to find Cooks distance on ArcGis or do I have to use SPSS?
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30 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 ...
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39 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 ...
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266 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 ...
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0answers
54 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 ...
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0answers
67 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 ...
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0answers
67 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 ...
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0answers
41 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