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

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1answer
26 views

How do I Calculate Grouped Percentiles or Batch percentiles in ArcMap?

My question is similar to this one which was answered successfully: Calculating Percentiles in ArcMap? My addition is how do I batch this solution for multiple files or apply a group-by feature to ...
1
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0answers
15 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, ...
1
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1answer
50 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. ...
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1answer
34 views

Counting points in concentric circle buffer zones of different sites in a map? [closed]

I produce concentric circles of 200 and 500 m buffer zones to see water points within each buffer zones. The buffer zones are created throughout my study area. How can I count the points found in ...
1
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1answer
49 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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1answer
31 views

Zonal Statistics as Table output is missing some polygons ONLY when run from Python script

I have a raster file from which I am attempting to calculate mean values for polygons defined in a shapefile. Using the Zonal Statistics as Table tool from within ArcGIS works great. My shapefile ...
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0answers
28 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 ...
1
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1answer
49 views

Unit of measurement from standard error prediction map

I am performing an ordinary kriging analysis and came out with the prediction standard error map. I would like to know the units of such map. Can anyone help me?
2
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1answer
47 views

How to calculate RMSE of geographic coordinates?

I've been working on my project and I stumble upon how I can calculate the Root Mean Square Error (RMSE) of geographic coordinates. What I have is a derived coordinates from processing LiDAR data ...
0
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1answer
23 views

Need statistics from US census [closed]

I am not sure if this is the right place to ask, if so please recommend a stackexchange, I am having a lot of issues getting the data approximations that I need for a report. I am looking for the ...
0
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1answer
68 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 ...
1
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1answer
52 views

QGIS equivalent to MapInfo Sum Attributes for selected vector objects?

I´m looking for QGIS equivalent to the basic MapInfo tool "Sum Attributes". I´ll explain what it does: For selected objects in a vector layer, a popup window shows basic statistics such as: - Sum ...
1
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1answer
27 views

Can I no longer see my view counts in the new dashboard?

The inset graphic shows the relative up and down of each day's views, but I can't see any numbers. I'd love to continue tracking my monthly stats.
2
votes
1answer
46 views

Disaggregating vector layer splits

I'm fairly new to GIS, but I've got the basics down. I'm utilizing QGIS and Python to calculate election statistics by legislative and congressional districts. I'm trying to aggregate precinct level ...
1
vote
1answer
47 views

Proof low deviations in DEM compared to point dataset

I am not sure how to achieve the following consistently: I have a regular distributed point dataset (surface elevations). From this I derived several DEM using QGIS IDW Interpolation method. Now I ...
0
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0answers
39 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 ...
2
votes
1answer
66 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 ...
2
votes
1answer
242 views

Calculate area weighted average of attribute in one layer by shape in another

For a project I am working on I would like to intersect fire station response districts with income data to determine the median income per response district. However the borders of the layers ...
1
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0answers
53 views

IDL 7.1.2; How to plot negative correlation in Taylor diagram [closed]

I am working on a model's run performance evaluation, three runs of GFDL-CM2.0 and five runs of GFDL-CM2.1 are used for temperature and precipitation for the years 1979-2000. The objective is to ...
2
votes
1answer
60 views

Create a grid with statistics of the merged shapefiles in QGIS

I operate with QGIS. I have to split the shape files of the buildings and the roads of a city into a grid of 500x500m per square and into each square I have to obtain the total free area, the total ...
2
votes
1answer
102 views

How to calculate the number of points with differing characteristic in a polygon in ArcMap?

I have a .csv (exported to .shp) database with about two thousand entries of points. One column in this database has certain values (e.g. a point can be 'ash tree', 'beech tree', 'elm tree', etc). I ...
2
votes
1answer
153 views

How to calculate zonal statistics from multi-band raster with no attribute table

I have a raster image (.tif) that is multi bands (35 band), floating point data type that does not have attribute table, and a grid shapefile of 107 polygon created by the fishnet function in ArcGIS. ...
1
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1answer
75 views

Statistics on [FID] from table window

Try to do this and you'll get an error message. However you can easily get statistics on [FID] using Summary Statistics tool. Somebody has a good explanation of this? Also note that from within the ...
4
votes
1answer
199 views

Calculating Percentiles in ArcMap?

I have a large polygon dataset (26,000) records with numerous attributes columns. I wish to calculate the percentile rank of each attribute. Say I have population_density in an attribute, is there a ...
1
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2answers
51 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 ...
1
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0answers
68 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 ...
0
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0answers
38 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.
1
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1answer
94 views

Does calculating statistics in ERDAS change raster values?

I've been under the impression that calculating or recalculating statistics in ERDAS doesn't actually modify an image, but I notice when I do this that when I look at the image file in windows ...
0
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0answers
16 views

line chart similar to Esri Histogram Time Slider [duplicate]

I am looking for a solution similar to the one provided by the Esri DIGIT class "HistogramTimeSlider" but instead of a histogram, I would like to use a line chart. Anybody seen a suitable reference?
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1answer
186 views

Calculating average NDVI

I would like to calculate average NDVI values. I have 3 values of NDVI: high:243 low:0 high:243 low:0 high:238 low:0 How can I use a a raster calculator to calculate the average valvue
0
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0answers
28 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
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 ...
3
votes
0answers
100 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 ...
3
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0answers
54 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: ...
3
votes
1answer
79 views

How to make zonal statistics model more efficient?

I've made this model, to assess some 500-600 rasters for one area, and spit out one huge table. So far, when testing it with 20-30 rasters as inputs it works, but now that I put in the full amount its ...
4
votes
1answer
30 views

raster statistics by line shape (vector)

I have a georeferenced area where I created 7 raster maps (classified with suitability values from 1 to 5) as I have 7 factors to check e.g. natural reserves, floods, slopes etc. From there I did a ...
4
votes
1answer
112 views

How to get counts from a table to produce a heatmap?

I am trying to create a heat map of doctors per zip code based on zip code. I have a table with the doctors and their zip codes, some of them repeating because there is more than one doctor per zip ...
2
votes
3answers
36 views

Raster statistics

In ArcMap, I have a raster layer representing site locations. I derived elevations values for the sites from a DEM. Now want stats on distribution of elevation values at those sites. How can I do ...
0
votes
3answers
380 views

Capabilities of the Analytical Hierarchy Process (AHP) in conjunction with the weighted overlay tool

I am making a prospective map of fossil deposits using the "Weighted Overlay" ArcGIS tool. Input factor rasters are mostly topographic in nature (elevation, roughness, TPI, etc). Initially, I had ...
2
votes
1answer
22 views

Two maps, one with classes and one with no classes. get the sum of one map into the classes of the other

I have two maps. One map has some classes and the other one is a raster with no classes. To illustrate, the map with the classes: 0-1, 1-2 and 3-4! The other map is a raster with values from 0-1000. ...
1
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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 ...
1
vote
1answer
37 views

Why am I getting small float numbers when aggregating points containing large integer values in QGIS?

I have a layer of points containing the centroids of European NUTS regions at NUTS 3, with population data in the atttribute table. I want to aggregate this population data to NUTS level 1, which is ...
0
votes
1answer
193 views

arcpy SearchCursor return a OBJECTID value not as an integer

I use summary statistics GP tool to extract the max OBJECTID from a feature layer. After that I use arcpy SerachCursor to get the OBJECTID value from the statistics, but the result returned is not an ...
1
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0answers
16 views

Calculation of RMS between two grids [duplicate]

I want to calculate the RMSE of two grids based on their z-value: a calculated and a reference grid. I do have the statistics: Cells, Range, Min, Max, Sum, Mean, Variance, St.dev. How could I solve ...
2
votes
0answers
120 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 ...
4
votes
1answer
188 views

Why covariance values are different in R and ArcGIS?

I've calculated covariance between 7 rasters using R and ArcGIS. It gives me different results. Each times covariance values from R are approximately 1.874 times higher than ArcGIS values. R - ...
4
votes
2answers
765 views

Zonal statistics for millions of overlapping polygons

I am running ArcGIS 10.1 with 64-bit GP on Windows 8.1 x64. I want to calculate the zonal statistics of buffer polygons based on parcels and a kernel density raster. The 4.7 million polygons overlap ...
2
votes
1answer
103 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 ...
5
votes
3answers
239 views

Is it possible to calculate statistics across multiple fields in arcpy?

The summary statistics command can be used in arcpy to calculate statistics - this tool runs against a single field, eg: SUM—Adds the total value for the specified field. Is there an ...
3
votes
2answers
539 views

How are kappa and overall accuracy related with respect to thematic raster data?

I recently calculated kappa (using confusionMatrix{caret} in R) between a thematic raster dataset at 1m spatial resolution and another at 30m spatial resolution. I was interested in quantifying the ...