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

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4
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1answer
89 views

Index express the similarity in shape between two data sets

I have two data sets. One is points in the blue curve. The other is points in the green curve. Now I want to find a property (P) or something else like index that has the following characteristics: ...
3
votes
1answer
102 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 ...
3
votes
1answer
108 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
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
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
votes
1answer
412 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 ...
3
votes
0answers
92 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: https://trends.builtwith....
3
votes
0answers
156 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 ...
3
votes
0answers
32 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 ...
3
votes
0answers
225 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
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 ...
2
votes
0answers
40 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.
2
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0answers
98 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 ...
2
votes
0answers
241 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
votes
0answers
77 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
votes
0answers
438 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
537 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
vote
0answers
33 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 '...
1
vote
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 ...
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 (...
1
vote
0answers
55 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 ...
1
vote
0answers
75 views

Explaining different results from Ordinary Kriging and Universal Kriging?

When using either methods to create a surface from the same set of observations, these surfaces differ from each other. Visually it can be seen in the differences of the following contours (...
1
vote
0answers
274 views

Using Python to compute the distance, speed, and time between coordinates (lat/long) using haversine formula and print results within .csv

I have a .csv file with 10 columns. The first column is titled Distance_Between_Points, the second column is titled Time_Between_Points, and the third column is titled Speed_Between_Points and all ...
1
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0answers
60 views

Raster distance for statistical analysis

I am trying to some kind of hedonic analysis. I need to calculate driving forces for new urban areas. In order to do this, i have a raster with new urban area's and one with existing urban areas (...
1
vote
0answers
75 views

Using linear regression for geospatial data?

Say, my database has three columns. A: county (300 rows with 300 counties as index), B: X (some independent variable in continuous scale, which is the average of everyone in that county), and C: Y (...
1
vote
0answers
31 views

Statistical bias arising out of only comparing US census block groups that have not changed (been split) over time?

Census Block Group ("CBG") study areas are notorious for changing over time. Even from 2009 to 2013, about 10-25% of the CBG's in South Carolina have not remained consistent over that time. Seeing ...
1
vote
0answers
53 views

Raster Area within a Polygon

using ArcGIS, I have a layer of overlapping polygons and a raster grid underneath. The raster is not a continuous grid - the cells are spread out. I simply need to calculate the total area of the ...
1
vote
0answers
241 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 ...
1
vote
0answers
125 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 ...
1
vote
0answers
51 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
612 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 ...
1
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0answers
156 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
109 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
153 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
197 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
vote
0answers
605 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 ...
1
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0answers
42 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
0
votes
0answers
13 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
0answers
53 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. ...
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 ...
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 ...
0
votes
0answers
36 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 ...
0
votes
0answers
72 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): head(...
0
votes
0answers
63 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 ...
0
votes
0answers
80 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 ...
0
votes
0answers
32 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
votes
0answers
44 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
85 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
99 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
79 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 ...