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

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3
votes
2answers
136 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
votes
1answer
46 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 ...
0
votes
1answer
17 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 ...
1
vote
1answer
36 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
vote
0answers
20 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.
3
votes
1answer
52 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?
2
votes
1answer
32 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
39 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 ...
1
vote
2answers
629 views

min and max values are not correctly calculated for DEM

I'm working with DEM in QGIS and need to know the min and max values of my data. In the Properties window, under the Metadata tab, the statistics section shows such values. However, I usually find ...
0
votes
0answers
63 views

How to calculate sums for all fields in a table? [duplicate]

Possible Duplicate: are there any methods can choose all field and make the SUM for each fields or I must do it one by one? Are there any methods that can calculate the summary statistic ...
0
votes
0answers
31 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
49 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
96 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 ...
5
votes
1answer
443 views

QGis Zonal Statistics Plugin NoData included in Calculations

I have been trying to use the QGIS zonal statistics plugin. My raster has a nodata value of -99999 and all other values are positive. After computing the mean zonal statistics there are a number of ...
1
vote
0answers
40 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
45 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
62 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
96 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
vote
1answer
56 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 ...
3
votes
1answer
114 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
vote
2answers
41 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 ...
2
votes
1answer
427 views

Accounting for Spatial Autocorrelation in ZINB Model?

I'm doing an analysis on disease in Chile. I'm using the rate as the Dependent Variable and both remote sensing and housing-type data as the Independent Variables. I have several questions regarding ...
1
vote
0answers
55 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 ...
3
votes
1answer
305 views

Sensitivity analysis for coarse scale GIS epidemiological model?

I am working on an epidemiological model with disease incidence rate as dependent variable and environmental factors as independent variable. Disease data is available at county scale whereas ...
1
vote
1answer
63 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 ...
3
votes
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 ...
0
votes
0answers
30 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.
0
votes
0answers
64 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
votes
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?
-1
votes
1answer
151 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
3
votes
1answer
318 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 ...
2
votes
1answer
84 views

resampled thematic map accuracy

I've generated a map of ecoregions based on some environmental data using a semi-supervised classification where I combined a statistical clustering with random forests to generate my map. I created ...
4
votes
2answers
607 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 ...
0
votes
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
votes
0answers
29 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
vote
1answer
930 views

What is the difference between nominal, categorical, ordinal, interval and ratio measurements?

Given the following examples, which are examples of nominal, categorical, ordinal, interval or ratio measurements? bushels of wheat per county vegetation type average maximum daily temperature ...
1
vote
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 ...
8
votes
4answers
7k views

How to calculate raster statistics for polygons?

how can I calculate sums, averages etc of raster-points (multi-band) per polygon of a vector-layer. I was told that this is called "zonal statistics". I tried that with QGIS first. There is a way to ...
3
votes
0answers
86 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
votes
0answers
51 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
77 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
27 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
97 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 ...
7
votes
1answer
170 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 ...
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
256 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
21 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
vote
0answers
34 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
32 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
155 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 ...