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

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15 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?
-1
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1answer
90 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
27 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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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 ...
1
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0answers
23 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: ...
2
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1answer
54 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 ...
3
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1answer
24 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 ...
3
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1answer
71 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 ...
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3answers
28 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
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3answers
77 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 ...
1
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1answer
19 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
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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1answer
27 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
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1answer
84 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
15 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
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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 ...
4
votes
1answer
131 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 - ...
3
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2answers
256 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
60 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
114 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
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2answers
142 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 ...
6
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1answer
115 views

Graphically depict statistical difference between thematic rasters

The graph shows a regression between two raster datasets with classified tree canopy cover: class 1 = 0-10%, class 2 = 10 - 20% ...class 6 = >60% (Figure 1, Figure 2). The spatial resolution for ...
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
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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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 ...
2
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1answer
52 views

Summarizing Table on 2 fields

I have a table of Census Blocks linked to ZIP4 values. I'm trying to create another table getting the unique ZIP4 values associated with each Census Block. I've tried using the Frequency, and Summary ...
0
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1answer
32 views

How to implement a Gaussian function in field calculator?

Are there any build-in functions like Gaussian or Epanechnikov functions in field calculator? Or I have to write that by myself?
0
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1answer
30 views

Calculating GRID Statstics

I have a GRID raster dataset with no calculated statistics. I have tried building pyramids and calculating statistics with no luck. What am I missing? EDIT: For those who don't understand: 1. ...
0
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2answers
150 views

Lengths of lines within individual but overlapping buffers?

I have a set of points for which I have created a 12 mile buffer. Eventually, I would like to know how many kilometers of road exist within each buffer zone individually? The problem I see going ...
1
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1answer
91 views

How to derive Z-score values for a given field

I have a shapefile with an attribute field with a range of numerical values. I would like to derive z-score values for this field within ArcGIS. Any tips?
0
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1answer
104 views

Counting all features in all layers of ArcGIS map to get grand total?

I have 20-50 polygon layers in an mxd and I want to find out the aggregated amount of all features (global count). The shapefiles which are the source of those layers are stored in different folders. ...
0
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3answers
83 views

ArcMap Change Values Greater than Standard Deviation of Mean to Zero

I have a feature class with greater than 1000 features and I would like to change all values greater than 2 Standard Deviations to a Zero. Seems like I could possibly use Field Calculator for ...
2
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2answers
85 views

Methods for hot spot or cluster analysis for multiple measurements at the same geographic unit?

I would like to find geographic clusters of zip codes where each zip code has a measurement of a person's age (integer), sex (categorical/binary), and if they recovered from a certain medical ...
0
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1answer
158 views

Get the different values assigned to a zip code

I have a map to which I added a zip code layer and another layer which contains values assigned to every square kilometer within each zip code. I'm trying to find out how many different values there ...
1
vote
2answers
110 views

Min - Max within a zip code (statistics by area)

I'm new to ArcGIS. I have created a layer representing zip codes and overlayed it with a layer containing some data points. I want to find the min and max value of the data points in each zip code. ...
0
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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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2answers
70 views

How to track ajax WMS requests in OpenLayers interface?

I'd like to track WMS requests on my openlayers web interface. How is it possible to log on my server or in Google Analytics every WMS requests (GetMap and GetFeatureInfo would be enough)? Then I'd ...
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
34 views

Applying Spatial Clustering test using R? [duplicate]

I’m very new to R so please bear with me: I have a set of area infested by a disease (AIS) annually data and I want to apply some cluster methodology to detect regions with similar (AIS) patterns. I ...
0
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0answers
53 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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1answer
147 views

Do I need to run regression in each samples separately?

I'd like to do smooth NDVI image by regression analysis; response of time series NDVI image to Julian date to represent the seasonal changes in NDVI as a function of Julian day. The time series NDVI ...
1
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1answer
68 views

How to analyse point data as covariate for areal data

I have two data sets: a) a set of polygons with areal data variables. b) point measures of various co-variates of interest (note I do not necessarily have a point for each polygon) How do I ...
2
votes
1answer
42 views

Overview of statistical maps/charts types

I know of a few ways to visualize statistical information on a map, like choropleth maps, prism maps or simply displaying little bar-charts or pie-charts near locations on a map. But there must be a ...
1
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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 ...
1
vote
1answer
59 views

Calculations from Feature Server and display values

Using the ESRI JS API I would like to apply some basic math based on the Shape.area of a feature and then return that calculation to the web-page. I can't see any reference to something even remotely ...
2
votes
1answer
228 views

How to create a x-y scatterplot from attributes in QGIS 2.0?

There are a few old packages that allow the creation of x-y scatter plots from attributes in vector data (Scattergram for 1.7) http://plugins.qgis.org/plugins/scattergrammidentify/ (SPQR for very ...
1
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1answer
153 views

What do “count”, “mean”, and “sum” in QgsZonalStatistics mean?

I am working with Qgis and making some analytics of lightdata. I've used these commands: rasterfile = qgis.utils.iface.mapCanvas().currentLayer().source() vectorlayer = ...
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?