Questions tagged [spatial-statistics]

The field of study concerning statistical methods that use space and spatial relationships (such as distance, area, volume, length, height, orientation, centrality and/or other spatial characteristics of data) directly in their mathematical computations.

Filter by
Sorted by
Tagged with
0 votes
0 answers
17 views

Spatial association between point and line layers [closed]

I have a point layer with an attribute indicating - the percentage of crime rates. I have a line layer showing the boundary of a country. I want to show that the closer one is to this country boundary ...
user avatar
  • 1
0 votes
0 answers
14 views

Modeling spatial relationships between two feature classes in ArcMap

I am using ArcMap 10.8. I am working on a project that involves a polygon feature class that represents mean income and a polygon feature class that represents the parks within a city. I want to model ...
user avatar
  • 1
4 votes
2 answers
161 views

Calculating mean value for points within polygon in QGIS

I have square polygons that follow the route of a boat. There is also a point layer with different measurements like salinity, temperature etc. Sometimes there is only 1 point inside the polygon, but ...
user avatar
  • 123
4 votes
1 answer
60 views

KNN for spatial data and two sets of coordinates

I'm trying to estimate an average value of distances to K nearest neighbors. I have two sets of coordinates and I'm trying to estimate the average distance from each point in one set of coordinates to ...
user avatar
  • 43
0 votes
1 answer
40 views

Google Earth Engine: Get summary statistics of an image for the whole globe (not for a region)

Is it possible to get descriptive stats for an image for the entire globe? I've been trying to google this but I generally find two types of answers: Sats over a region using image.reduceRegion(..) ...
user avatar
0 votes
0 answers
19 views

Storing movement vectors in DB

I'm not sure if this question is applicable to here or the stats exchange. Maybe some GIS folk have taken a good look at GIS stats? I've got a postgres+postgis+timescaledb database that has billions ...
user avatar
  • 1,211
0 votes
0 answers
10 views

QGIS - Randomisation and multiplication of a polygon with CLC files

I am using QGIS 3.22 and the Corine CLC vector files for years 2006, 2012 and 2018. I Want to generate a polygon with a random shape, which would be exactly the same size of the polygon circled in red....
user avatar
  • 399
1 vote
0 answers
24 views

Nearest Neighbour Index (NNI): how to compare values & in depth explanation of how to calculate expected mean distance

I have two questions regarding the ‘Nearest Neighbour Index (NNI)’, sometimes also referred to as ‘Nearest Neighbour Analysis (NNA)’: I have calculated the ‘Nearest Neighbour Index’ for 4 different ...
user avatar
  • 542
0 votes
0 answers
23 views

Spatial similarity measure with continuous data using Python

My question is similar to an unanswered one at Quantifying similarity between two independent areas using R. I'm doing a machine learning project with PyTorch and am looking for a way to compute ...
user avatar
0 votes
1 answer
21 views

What is the "block" argument in Automap R package?

Sorry for not providing a code. I am asking a question that do not need a written chunk of code. I am performing climate interpolation using the automatic semivariogram fitting offered by Automap R ...
user avatar
  • 99
2 votes
1 answer
137 views

Error with function argument when using extract function in R

I am using the script described here to try to extract a count of raster cells within polygons in a shapefile. This code worked for me yesterday but today I am getting the following error: Error in ...
user avatar
  • 51
0 votes
1 answer
44 views

Do you need to factor in projection into area calculation in Google Earth Engine (GEE)?

I'm interested in calculating the area I have classified of a certain class. Do you need to account for projection to assess class area or can you run the following code and it will be accurate? I'm ...
user avatar
0 votes
0 answers
6 views

STARS toolbox segment PI returning nulls

I am working to create an isoscape using the STARS toolbox in ArcGIS, and have come back to it to rerun a few things. I had previously run the segment PI (proportional influence) using watershed area ...
user avatar
1 vote
1 answer
37 views

Using weight component in Moran I calculation

I'm trying to understand the Moran I calculation, and there is something I don't understand. In this tutorial, Moran I described as the slope value of the correlation between one polygon to the ...
user avatar
  • 1,797
0 votes
0 answers
24 views

Discrepancies in size of area for Brownian bridge model

I want to get the size of some animal tracks using a Brownian bridge movement model. However, I've noticed that when I combine my data into a single object the size of the area differs compared to ...
user avatar
  • 41
1 vote
0 answers
31 views

Is it possible to segment data in QGIS by adding shapefiles and then exporting both as one (csv) dataset?

I have this global temperature data set https://1drv.ms/u/s!ArVyXA5cSMj2h6h0GCSsNGKCsAYpSg?e=bZUaxx (sorry it's almost 1GB, but this light data set is much smaller and is very similar, if you just ...
user avatar
2 votes
0 answers
21 views

Comparing Heatmaps over time

We have a huge dataset of mobile users (tourists) and want to see how the density in a city has changed (from one spot to another) before during Covid. Of course we can create a heatmap for different ...
user avatar
1 vote
1 answer
166 views

Creating formatted chart for Confusion Matrix using Google Earth Engine

I was curious how to create a formatted Confusion Matrix: (https://developers.google.com/earth-engine/apidocs/ee-confusionmatrix) I've completed my Supervised Classification, and I've created a ...
user avatar
2 votes
1 answer
50 views

Getting percentage of string values for point layer within polygons of another one

I have two layers. One with polygons of areas of a city. Another one - with points corresponding to buildings. In point layer there is a field with the names of management companies of that buildings. ...
user avatar
  • 505
0 votes
0 answers
34 views

What tools/methods are there for spatial autocorrelation with raster data in ArcMap?

I'm using high resolution LiDAR data to find patterns in canebrakes. My hypothesis is that cover (represented by point density per cell) will be more homogeneous between height strata in canebrakes ...
user avatar
0 votes
0 answers
24 views

Getting raster statistics without clipping in ArcGIS Pro

I am using the ESRI 2020 landcover dataset in ArcGIS Pro. I also have a shapefile layer with the countries of the world. What I am trying to do is to report the landcover per country, but without ...
user avatar
  • 335
0 votes
0 answers
53 views

Can the Getis-Ord Statistic really be considered a measure of spatial autocorrelation?

The Getis-Ord statisic G_i(*)= \Sigma_j w_{ij} x_j / \Sigma_j x_j basically calculates a geographically weighted average at some point. Is it fair to say that it is rather a measure of spatial ...
user avatar
0 votes
0 answers
40 views

Stein's parameterization matern model kriging SAGA in QGIS

I performed autovariogram in R. It gave me the output seen below. It suggest using a matern model-Steins parameterization (indicated by the "Ste"). I would like to try the kriging tools by ...
user avatar
0 votes
1 answer
53 views

Counting points in polygon using separate attribute values in ArcGIS Pro

I am trying to determine the different land surface types within a set of polygons. To do this I converted my land surface type raster layer to points. So now I have a polygon layer (hexbins across my ...
user avatar
  • 23
0 votes
0 answers
43 views

Null standard errors in multiscale geographically weighted regression

I'm currently conducting an multiscale georgraphically weighted regression using the official python based package by Oshan et al.*. However, i ran into a slight problem. Whenever an explantory ...
user avatar
0 votes
0 answers
47 views

Want to calculate percent cover of land use categories within buffer areas?

I have point data and a land use map. I created 100m buffers around each point, I now want to calculate the percentage of cover represented by each land use category detected within the buffers. Would ...
user avatar
4 votes
1 answer
206 views

How to assign a neighbour status to unlinked polygons

This question is, in part, a follow up to: https://stackoverflow.com/questions/57269254/how-to-impute-missing-neighbours-of-a-spatial-weight-matrix-queen-contiguity I have a .shp similar in structure ...
user avatar
0 votes
1 answer
35 views

Calculating percentage of points per raster band (elevation, slope, aspect...) in QGIS

I have a series of rasters expressing environmental variables, for example, elevation. I have used the tool 'add raster values to points' to classify the sites according to the bands (10) I have ...
user avatar
2 votes
1 answer
121 views

Rendering three-composition raster map with ternary colormap using R

Say there are three raster maps, representing percentages of sand, silt and clay respectively. The three values for each cell are hence summed up to 1. I want to use one raster map to characterize the ...
user avatar
1 vote
1 answer
77 views

Fitting a variogram for Kriging in R

I want to fit a variogram of my data for kriging. Here is what I have so far: library(sp) library(rgdal) require(gstat) setwd("C:/Users/49151/Desktop") #import data data <- read.csv(&...
user avatar
0 votes
1 answer
71 views

IDW plot miscalculation

I want to perform IDW in R and plot it with ggplot. Here is my code so far: library(tidyverse) kerpensample_df <- read.csv("C:\\Users\\49151\\Desktop\\kerpentest0909x.csv", ...
user avatar
0 votes
0 answers
28 views

Local Moran’s I vs Getis-Ord Gi* for Cluster/Hotspot Analysis

I was wondering if someone could perhaps help explain the difference between these two methods and when it might be more appropriate to use one vs the other for cluster/hotspot analysis? I understand ...
user avatar
0 votes
0 answers
24 views

GRASS QGIS v.vect.stats returns NULL for all polygons

I'm running v.vect.stats from Grass using the processing toolbox in QGIS to take an average of a point layer attribute for points falling within a set of polygons. After running the algorithm a ...
user avatar
  • 133
3 votes
1 answer
37 views

Field name for stats to be calculated not appearing using v.vect.stats

I'm trying to calculate the average value for an attribute of a set of points that fall within a set of polygons using v.vect.stats from GRASS. I've checked the attribute table of the point layer ...
user avatar
  • 133
0 votes
0 answers
363 views

R pivot_wider: Error in Ops.sfc(xi, xj) : operation > not supported

I've rerun some data and am now getting this cryptic error message when trying to transfer my sf object from long to wide table format. Error in Ops.sfc(xi, xj) : operation > not supported Does ...
user avatar
0 votes
0 answers
28 views

How to calculate the minimum value from set of group of points

I have a set of groups of points with similar X and Y values. I want to extract the point which holds the minimum elevation value. Like in this below pic, I want FID 226 which holds the minimum value ...
user avatar
  • 385
0 votes
0 answers
29 views

Modeling Correct Spatial Relationship using Hot Spot Analysis in ArcMap

I used the Hot Spot analysis tool in ArcGIS Online to identify the cities and townships where significant clustering of population growth ("hotspots") and population decline ("cold ...
user avatar
3 votes
1 answer
87 views

Determining who and why certain data was mapped in OpenStreetMap

I am writing a masters thesis about estimating solar potential based on open source resources. Part of my methodology is to use a sample of buildings to estimate solar potential for the whole city. ...
user avatar
  • 39
0 votes
1 answer
40 views

Interpreting semivariogram from ArcGIS Pro

Am having an output for semivariogram from ArcGIS Pro as per below. However, the distance looks small. Is there a way to adjust the distance? Not only that, how best can I interpret the x and y values ...
user avatar
0 votes
0 answers
27 views

Calculating focal sum with R returns error saying wfFocalSum is not found

I am attemtping to calculate a focal sum in r using a binary raster, ones and zeros, but r is returning the following errors: Error in .local(x, row, nrows, ...) : validRow(x, row) is not TRUE Error ...
user avatar
  • 83
0 votes
1 answer
53 views

Comparative analysis between two landcover classifications from different models in R

I have two landcover classifications computed via random forest and maximum likelihood classification models in R. I am trying to compare the two in R. One way I thought was to do simply compute the ...
user avatar
1 vote
0 answers
23 views

Viewing PCA variable loadings using ArcMap

I am trying to use the PCA function in ArcMap 10.7 (or similar builds). I am accustomed to receiving variable loading scores for each PC in non-GIS statistics. These are the fundamental data that help ...
user avatar
0 votes
0 answers
379 views

Co-kriging in R

I am trying to do co-kriging for my rainfall with arsenic data. Arsenic is a target variable. I have used the code below to generate an interpolation grid, but I was not able to generate the co-kriged ...
user avatar
1 vote
1 answer
34 views

Method for testing difference in raster attributes between polygons

Say I have a raster with attribute values over some spatial area. Also, say I have circular polygons of varying sizes contained within the raster's area. What would be the proper method to test if the ...
user avatar
1 vote
1 answer
74 views

Comparing the strength of spatial autocorrelation of two datasets on the same studied area

I want to compare the strength of the spatial autocorrelation of two sets of values that are located on the same area. The data are individual growth rates. I want to compare the strength of the ...
user avatar
  • 21
1 vote
0 answers
39 views

QGIS, zonal statistics value is missing for a polygons

I am using India district shapefile 2011 to extract rain data. The rain data comes in point layer which I have converted to raster using "IDW interpolation" to get continuous rain data. To ...
user avatar
  • 11
0 votes
0 answers
89 views

NA in the summary of a spline correlogram in the package ncf and doubts about distance units

I am a PhD student currently working on some spatial analysis. I work with a free range population of starlings that breed in nest boxes. Our aim is to know if reproductive success (i.e. number of ...
user avatar
0 votes
0 answers
26 views

Seeking R Equivalent to ArcMap Highest Position

I can easily do this process in ArcMap but am hoping I can replicate it more easily in R. I have a RasterStack with values of temperature for every year over the last 100. I know I can easily create a ...
user avatar
  • 1
1 vote
1 answer
170 views

How to extract raster class values from a multi polygon shapefile in QGIS

I'm trying to perform a laborious task to get the class values of a raste overlaid on a multi-part shapefile. I have a raster with values rated from 0 to 8 for a Main Basin. I also have a shapefile ...
user avatar
1 vote
0 answers
39 views

Statistical comparison between two maps with aggregated average observations and average estimates from a model on a 1 x 1 km² grid

I've been searching for methods for the past two days, but I couldn't find something usefull, so I hope someone could help me out: I've got two datasets in python containing PM2.5 values: Dataset ...
user avatar

1
2 3 4 5
13