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Questions tagged [spatial]

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.

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My data is clustered in space, how can I account for that in a GAMM?

I am modelling whether a bird nest is build or not based on the date it was built, the geographical coordinates where the nest was built, and using the year when the nest was built as random effect - ...
Teresa's user avatar
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0 answers
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Environmental filtering versus spatial resampling in species distribution modeling

I am building species distribution models using machine learning models based on GBIF data (presence-only data) and working on a very large spatial scale, encompassing all of North America. Before ...
Marine Régis's user avatar
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1 answer
33 views

EM-algorithm for spatial data

I am very new to Geostatistics (Modeling spatial data) and have some questions: 1- I found that in many literature, the spatial random field is divided into spatial bins. That is, suppose I am ...
Dr. Statistics's user avatar
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28 views

State space models and Kalman Filter

I have the following model specification: $y_t = \mu_t + v_t,$ $\mu_{t+1|t} = \phi \, \mu_{t|t-1} + k\, v_t $ where v_t= y_t - mu_{t|t-1}, v_t|F_{t-1} ~ tv(0, sigma^2). I was asked to provide the ...
user414120's user avatar
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41 views

Unbiased Estimator of Nugget Effect

Question: I am trying the measure the nugget effect, which is parameterized by $(1-\lambda)$ in the following variance-covariance used to describe the multivariate normal distribution of my n-...
A Friendly Fish's user avatar
2 votes
0 answers
103 views

dubious diagnostics in species distribution modeling with mgcv gam

I am doing some marine species distribution modeling with gams and mgcv in R. The diagnostics from gam.check(), and concurvity() seem dubious. Are there issues with the specification of the model, or ...
Thanasis's user avatar
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17 views

How to compare multiple point patterns of the same realm resulting from different clustering methods?

I have a dataset of 500 sampling points to which I apply multiple different clustering methods for categorization. How can I compare the resulting spatial point patterns of cluster group labels? I ...
jlklein's user avatar
1 vote
1 answer
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Quantifying (observed) spatial clustering?

I am looking for some advice regarding spatial statistics. I have a large dataset with multiple samples across 5 different conditions. Each sample is composed of different point types in 2D space. For ...
stellaria's user avatar
1 vote
1 answer
47 views

Derivative of Linear Model with respect to Residual

I am looking at two sections on the wikipedia page for total least squares, specifically: #Allowing_observation_errors_in_all_variables and #Example I have two questions, the first is how does one ...
A Friendly Fish's user avatar
1 vote
0 answers
18 views

How to estimate a feasible Generalized Error-in-Variable Model (combine deming regression/TLS and f-generalized least squares)

I have observational data with spatial structure. A hypothetical dataset could be brain mass for 100 species of birds and body mass for those same species. The data has spatial structure because ...
A Friendly Fish's user avatar
0 votes
0 answers
6 views

GWR on spatially joined attributes

I am new here and am trying to build and compare a couple models using spatial data for estimation (GLM and GWR). I am trying to estimate counts using a training dataset that contains observations on ...
Juan P FZ's user avatar
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2 votes
2 answers
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Data modelling as a surface

I want to model waste generation in a city using data from the containers. I have the location and fill levels of each container over time. My idea is to use the average amount of waste in each ...
pato's user avatar
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28 views

How to know whether I should use DiD or Spatial RDD?

I'm quite new in econometrics. I want to study a nationwide policy change at the city-level. In year T-1, cities are divided in three zones (green, orange, red) depending on their tension on the ...
Yan's user avatar
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5 votes
1 answer
122 views

Using GAM for hotspot mapping

I’m going to preface this with, I’m no Generalized Additive Model or spatial statistics expert … I know enough to be “dangerous” … maybe that’s a bad thing 😉 Today I had a little bit of a thought ...
Paul Julian's user avatar
2 votes
0 answers
21 views

Smoothing spatial data for privacy issues

I have a dataset with about 6000 observations related to municipalities. The structure of the dataset includes four columns: the municipality code, the number of businesses in the municipality, the ...
Luigi's user avatar
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1 vote
1 answer
45 views

Hierarchical clustering of a distance matrix with element weights

I am computing a hierarchical clustering of some geospatial data. I need to add in an element weighting to the approach. My current approach is: I compute temporal cross-correlations between my N ...
JoshD's user avatar
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1 vote
1 answer
83 views

What is the name/terminology for this application of OLS regression

I don't come from a statistics background and was instructed to follow these steps to fill in missing data. I'm wondering if there is a name for this specific method so that I can learn more of it and ...
code_monke's user avatar
4 votes
2 answers
54 views

Forecasting a series that comes with uncertainty

I have a time series resulting from a spatiotemporal aggregation on the spatial domain. As a result, I have a central measurement (let's say mean average) and a dispersion (let's say standard ...
Ricardo Barros Lourenço's user avatar
1 vote
1 answer
41 views

Limit of Ripley's K function as r goes to infinity?

Considering the Ripley's K function as used in spatial point-process analysis, or the closely related L function, I am wondering what the limit of the function is as r approaches infinity. I am aware ...
Sriram Ramamurthy's user avatar
1 vote
0 answers
17 views

Joint Distribution Formulation of a Spatial X, Spatial Y, and Spatial Error Model

Introductory Problem: I have $n$ points in 3-D space, where I know their X and Y coordinates (not Z), and therefore the distances between points in those 2 dimensions. Each of the three dimensions has ...
A Friendly Fish's user avatar
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0 answers
31 views

Negative log likelihood cholesky decomposition

The code in question comes from Spatial Data Science by Pebesma and Bivand. I can pretty much understand what it says except for the last line. How does this give the negative log likelihood? I've ...
R Walser's user avatar
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1 vote
0 answers
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Out of sample testing Geographically Weighted Regression

I have spatial data on property prices and I've fitted a GWR, calibrated on all points. I haven't seen cross-validation or out-of-sample testing approaches applied to many GWR models in literature, Is ...
statmaj's user avatar
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0 answers
37 views

How to calculate AIC of a spatial panel model in R?

This may be a better question for Stack Overflow, but I think a statistics answer may be warranted here: I have built some spatial panel models in R using the ...
geoscience123's user avatar
1 vote
0 answers
50 views

Sampling from a very high dimensional Gaussian

I would like to a sample from a Gaussian $N(0,K)$ where $K$ is a kernel gram matrix, so that $K=[K_{ij}]$ with $K_{ij} = k(x_i,x_j)$ for some positive definite function $k$. The first issue is that ...
WeakLearner's user avatar
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0 votes
1 answer
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Including location dummy variables in Geographically Weighted Regression

I am modelling house prices using individual observations of property sales (not polygon data). Does it make sense to include dummy variables for postcode areas as parameters in the GWR model?
statmaj's user avatar
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2 votes
1 answer
41 views

NA results after pooling estimates and coeff of mixed effects cox model from MICE imputation dataset

I need your help with my problem. So, after step of imputation missing data through MICE method, I got multiple imputed dataset. Then, I pooled the estimates and coefficients with mixed effect cox ...
Hoang-Giang Pham's user avatar
1 vote
0 answers
26 views

Proposal parameterization accuracy for Importance Sampling

Suppose I am fitting a Bayesian mixture model that's structured as follows: $$ Y_i | (z_i = k) \sim \mathcal{N}(\mu_k, \sigma_k^2), \quad k = 1, \cdots, K $$ $$ z_i \sim \text{Mult}(1; w_{i1}, \cdots, ...
BasMts's user avatar
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0 answers
15 views

Multivariate mixture models with INLA: Relating CAR random effect to the MVN covariance matrix

For a research project I am trying to implement a multivariate mixture model on areal data using Integrated Nested Laplace Approximation (INLA). Let $y_{i,d}$ be a data point, where $i = 1, 2, \cdots, ...
BasMts's user avatar
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2 votes
1 answer
137 views

GAM model with spatial account via MRF

I am starting to read a little about generalized additive models and how spatial dependencies can be incorporated into the model, I'm reading Generalized Additive Models An Introduction with R from ...
Raheshi Knuwga's user avatar
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0 answers
19 views

Confirming the validity of a point process model

I have a question regarding a point process model I generated for a biological point pattern exhibiting repulsion and attraction at different scales. My goal for this model was to generate simulated ...
spatialanalysisquestions's user avatar
2 votes
0 answers
127 views

Seeking Guidance on Constrained Input Modeling for Soil Moisture Correction Using Rainfall Observations

I find myself immersed in the intricacies of working with 2D modeled fields (images) representing soil moisture in regions where direct observations are unfortunately absent. However, there is a ...
Seyed Omid Nabavi's user avatar
0 votes
0 answers
24 views

Matern covariance increasing with smoothness

Consider the Matern covariance function with the following parametrization: $$C_{\nu,\phi,\sigma}(h) = \sigma^2 \frac{2^{1-\nu}}{\Gamma(\nu)}\left(\sqrt{2\nu}\frac{h}{\phi} \right)^\nu K_\nu (\sqrt{2\...
Tommy Tang's user avatar
2 votes
0 answers
44 views

How should I combine “typical” and “yesterday” self-reports?

I have inherited a long-running survey with two measures of individual behavior. Edits: clarifying that this is not about drinking behavior; it’s not, and I only used that to try and illustrate. It ...
dholstius's user avatar
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1 vote
0 answers
38 views

Image Blur - Disc Kernel [closed]

I'm trying to use the blur() function from the spatstat package in R to blur an image. One ...
BurlyPotatoMan's user avatar
0 votes
0 answers
41 views

Imputing missing observations of zip code level data

I am looking for a sufficient imputation method for missing observations in my zip code level data, using R. I have a random sample consisting of households which live in different zip codes within ...
Ottibanane123's user avatar
0 votes
0 answers
14 views

Spatial autocorrelation weight matrix for heatmaps

I am not an advanced mathematician and I'm very new to spatial autocorrelation. So I apologize if my question seems primitive in any way. I'm looking for ways to quantify the distribution similarity ...
Saeed Aram's user avatar
2 votes
2 answers
43 views

Test statistic to assess the of spatial structure of clusters

I have a series of $n$ observations $i_{1},i_{2},..,i_{n}$, approximately spread across 10 different regions. Each $i$ has an associated $X$ and $Y$ coordinate value in 2-D Cartesian space. Each $i$ ...
user438383's user avatar
1 vote
0 answers
22 views

Spatial autocorrelation of car crashes and traffic safety complaints in python

I am admittedly new to spatial autocorrelation and I did this research myself so apologies if this is completely noob behavior. I am trying to determine if there is a correlation between the location ...
Bar Zavin's user avatar
0 votes
0 answers
25 views

Accounting for spatial dependence on 2D surface embedded in 3D using GAMs

I want to infer if a dependent variable (DV) can be predicted by several independent variables (IVs). Their relationship is non-linear and monotonic so I chose to use a GAM. Using the gam() function ...
avaruus's user avatar
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0 votes
0 answers
22 views

How to test if a particular frequency is significant or not in a fourier frequency spectrum

I have got a timeseries data with which I plotted a frequency spectrum and I could eyeball all the significant peaks (significant frequencies) in the plot. But I want to do this for a spatial data (...
arya lakshmi's user avatar
0 votes
0 answers
23 views

What is the correct way to incorporate sampling weights into a spatial regression?

I want to know what the proper procedure is for incorporating sampling weights into a regression. I am running a spatial regression using survey data in R. I'm using the function ...
mirrror's user avatar
  • 43
2 votes
1 answer
28 views

R joincount with non-integer counts

I am using the R function joincount.multi from spdep to look for spatial autocorrelation with my data. The joincount column is ...
Stephen Clark's user avatar
0 votes
0 answers
25 views

Calculate the correlation between two Space-Time Series

What method would be employed to calculate the correlation between two space-time series? For example, dataset 1 = a set of space-time points relating to cases of disease 1 and dataset 2 = a set of ...
Daniel J's user avatar
0 votes
0 answers
23 views

How would you deal with sparse and scattered 2d data in a way that makes physical sense?

I am currently analyzing rainfall data which is in longitude/latitude/value format i.e. a 2d matrix. That is, I have a series of values x,y,z such that ...
requiemman's user avatar
1 vote
0 answers
39 views

How to get plot of Ripley's K function (Kest) for temporal data in R? [closed]

I have the temporal data of Landslide events in CSV format. My data consists of Year, Month, and Day of events. I want to see if there is temporal clustering for events or not by using Ripley's K ...
Khushboo Kumari's user avatar
0 votes
0 answers
38 views

Alternatives to Gaussian Process for spatial count data

I have some 1-D spatially distributed count data, and I'd like to model it as a function of a relatively smooth latent variable. I've managed to get a version of this to work using a Gaussian process ...
Tarquinnn's user avatar
  • 111
0 votes
0 answers
4 views

test fof relative global impact of latitude and altitude on a variable, should I account for spatial dependence?

I want to test for relative global impact of absolute latitude and altitude on a variable that ranges from 0 to 1 (six possible values). I have thousands of observations sampled across the world. I ...
Agus Camacho's user avatar
0 votes
0 answers
10 views

How to model risk with presence-only data?

I'm working on a dataset of bird electrocutions. There are 300 instances of electrocuted birds and I have a range of environmental data that I want to input as my predictor variables. The aim is to ...
adkane's user avatar
  • 1,021
0 votes
1 answer
30 views

Combining location based probabilities from GPS data

I'm working with GPS data and have billions of GPS points stored in a DB. I'd like to be able to use this to create a class likelihood function that I can use somewhere else as as a visualisation or ...
RedM's user avatar
  • 111
2 votes
0 answers
84 views

Coefficients interpretation of survregbayes

I used the function survregbayes from the package spBayesSurv in R to perform a spatial accelerated failure time model with CAR ...
Ste's user avatar
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