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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1answer
26 views

Using direction of motion as a variable: What do do with undefined/infinite slopes?

I have a list of x,y coordinates representing an object's motion through 2d space. I need to do statistics where I use the direction of motion (slope) as a covariate to my variable of interest. ...
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34 views

Can't properly estimate parameters from simulation [closed]

I'm having a problem and I can't figure out why the code behaves as it does. I'm simulating a clustered process in R using the package ...
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0answers
13 views

Logit Model for panel data [r]

I would like to ask preferably preferably econometrics and statistics community about logit model for panel data. When dealing with panel data one must take into account individual effects (...
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10 views

trimming window in Foxall G-function and J-function in R spatstat

I am using the Jfox function in spatstat to explore the distance of points in a point pattern to the nearest polygon between a ...
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12 views

Spatial modelling: distribution of the random effects?

I am working on a spatial regression model: $$y_{ijk} = x_{ijk}^T \beta + u_j + v_k + e_{ijk},$$ where $y_{ijk}$ is the response for the $i$th individual living at region $j$ and working in region $k$...
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1answer
41 views

Combining two distance matrices for clustering

I'm looking to see if I can cluster geographic regions by a variable, such as losses. For example, I have 5 regions with the following amount of losses: Region 1 with \$500,000 in losses. Region 2 ...
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1answer
38 views

Does it make sense to consider ratio of pair correlation functions of two point patterns?

I have two point patterns, one is real data, the other one is simulated data from a model I constructed for the real data. Now I want to see if the second order property of the model matches that of ...
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3answers
60 views

In spatial data, does unevenly distributed data create model bias?

The scenario: Suppose there is a square shaped region with three cities in it. A dataset is collected by citizens, who collect data where they live. Thus, data is collected much more heavily in those ...
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14 views

Low k-indeks in gam.check regardless how large the basis dimensions in gam analysing spatial data

I'm trying to fit a gam with spatial point data with the mgcv R package. When I check the gam with the gam.check function one of my variables appears to have a too low K (i.e. k-index < 0.6). Doesn'...
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1answer
11 views

Interpretation of Clark-Evans test and Hopkins-Skellam test (complete spatial randomness)

When I’am calculating a Clark Evans or Hopkins-Skellam test to test for complete spatial randomness a value with R/A < 1 signifies a clustered point pattern; R/A = 1 would be a random point pattern....
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8 views

How can I measure how my clumped my spatial data are?

If I have spatial data how can I measure the degree to which the points are clumped? ...
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54 views

Clustering of (mostly) spatial data, with “un-mergeable” constraints

I have data from field surveys, each representing the location of a bird, together with a date. I need to cluster the data based on distance (eg. < 120m). However, there are further constraints: ...
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10 views

Machine Learning: 1-way ANOVA from data collected where all samples are not independent?

I am analyzing machine learning imagery classification by using 3 different algorithms to classify imagery and a sample of ground-truth points to collect an overall classification accuracy. I wish to ...
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1answer
34 views

What relationships do spatial statistics share with time series analysis?

Spatial statistics is often discussed in tandem with time series. How are the two related? Do they share methodologies? Do overlap in assumptions or conditions of data?
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What is a good reference for Bayesian time series and/(or separately) spatial statistics at a graduate level?

(as title) I am currently looking at Bayesian Forecasting and Dynamic Models by Harrison and West. Is this text (published 1989) still relevant in that the fundamentals or core principals have not ...
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8 views

Local or global Moran's I minimum neighbor connectivity rules of thumb and justification

I am trying to run a univariate local Moran's I (in GeoDa) and I'm questioning my spatial weights, trying to do different neighbor counts / distances in increments and evaluate my results. I was ...
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22 views

Smoothing methods for geographically aggregated data?

I have some Canadian census data with various statistics defined by dissemination block. These blocks are irregular in shape since their boundaries are based on the road network. I thought it would be ...
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33 views

Time Series Analysis for Coordinates using LSTM

I have a dataset in which ids of locations connected with corresponding latitudes and longtitudes. I want to predict next location of the activity after training my LSTM model. However, feeding the ...
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0answers
23 views

“Jumping” among several interpolation techniques?

I am comparing several interpolation methods using monthly climatic data, through RMSE and a 10-fold cross-validation scheme. What I'm observing is that the performances vary from one month to ...
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15 views

Creating non-negative definite matrix for multivariate spatial random field?

I am trying to model a spatial multivariate (three variate) random filed. I have defined correlation matrix using LMC as function of distance lag of interested points $\mathbf{C(h}{{\mathbf{)}}_{3\...
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1answer
33 views

Neighborhood matrix in spatio-temporal model

I am attempting to create a neighborhood matrix (poly2nb in spdep) in R to use either for a GAM or an INLA. As I have spatio-...
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5 views

Conditional Autoregressive (CAR) model in a non-Bayesian framework?

The Conditional Auto-regressive (CAR) model is used to capture spatial variation in a dataset. Most of the works I have seen considering CAR model is in Bayesian framework. My question is can the CAR ...
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1answer
14 views

Comparing log likelihood & AIC for two spatial error regression models with the same dependent but different independent variables

I have two spatial lag models using the same dependent variable (average income) and different independent variables (1- living environment deprivation; 2- education deprivation) for towns in the UK. ...
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10 views

spatstat and stpp for one-dimensional spatial data

I have one dimensional spatial data, and the spatio-temporal analysis is two dimensional. 1) Does Ripley's K function change because I no longer have a circular spatial region but a line segment and ...
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1answer
17 views

how to determine number of objects in the area

The problem is to determine number of objects in the area defined by polygon of arbitrary shape. Suppose trees are planted randomly in a rectangular area. The trees are being eaten by some bug and ...
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0answers
18 views

Metric for dispersion that corrects for sample size

I'm looking for a metric to measure dispersion of a set of points in 2D (or higher dimension) space. This post gives some examples, such as the sample mean of all points to be the center point and ...
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1answer
33 views

What exactly is meant with “data parameters” in Bayesian hierarchical models?

Please excuse me if the question in unclear, but I am seeing much nomenclature for the first time and am somewhat confused. I am reading "Statistics for Spatio-temporal data" by Noel Cressie and ...
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74 views

Pope effect on pizza - Regression with presence absence and similarity data as dependent variables

I'm trying to figure out the right way to set up a regression when the dependent variables are presence absence data (of pizzas), and the similarity between the present pizzas. Bear with the story: ...
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24 views

Difference between MORAN.TEST and LM.MORANTEST functions R

I need to check the spatial autocorrelation in a GLM but I'm confused about which is the function that I need to apply. I get different outputs from each one of them. I think that in the case that I ...
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1answer
43 views

Reducing the dataset size for KDE

I have GPS data, so 2 coordinates, and I want to estimate the busiest places (i.e. the places with more data points). However, I have a lot of points: currently ~4 million for 12 days, and I will be ...
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2answers
63 views

Poisson process on an $n$-sphere

I have an algorithm that embeds data points into Euclidean space. If I norm these points then they will lie on the unit $n$-sphere, where $n+1$ is the dimensionality of the embedding space (generally ...
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15 views

Correlation Between Surfaces

Suppose I have a set of data that defines a three dimensional surface for each point in time. So you can imagine a surface that is continuously changing across time. Suppose I have a second surface in ...
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0answers
44 views

Adjust spatial autocorrelation in multilevel logistic regression using autocovariate in R

In the large volume of cluster data (i.e. 300K individuals are nested within 800 districts) with a binomial outcome variable (...
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0answers
46 views

Understanding the kdist graph used to select DBSCAN epsilon parameter

I need to use DBSCAN for my research and am having trouble understanding the kdist graph used to select the epsilon parameter - specifically, I do not understand what is happening behind the scenes ...
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0answers
27 views

How can I use spatial heterogeneity within regions as predictors about those regions?

Please forgive if I am misusing the term "spatial heterogeneity". I am trying to predict county level crop productivity using satellite acquired vegetative health (NDVI). Since this is pixel data, I ...
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20 views

What is the best way to model a spatialtemporal (3d) problem?

A very common problem in machine learning is that we have time variables. For this we use more statistical approaches like ARIMA or more ML approaches like LSTM. A sophistication of a time series is ...
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2answers
122 views

Finding $\mathsf P(\textbf{Y}\mid\textbf{Z})$ where $Z_1,Z_2,\ldots,Z_n$ are conditionally independent

As an extension of my previous question which is described below... Assume $Y_1$, $Y_2$, $\ldots$ ,$Y_n$ are random variables over a regular lattice indexed by $i= 1,2,\ldots,n$ where $Y_i\in\{...
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1answer
70 views

Finding conditional probability of an individual component of a joint distribution

Assume $Y_1$, $Y_2$, $\ldots$ ,$Y_n$ are random variables over a regular lattice indexed by $i= 1,2,\ldots,n$ where $Y_i\in\{1,2,...,K\}$. Let the probability of a particular configuration $\...
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1answer
75 views

how to interpret/report estimated spatial lag coefficients

I estimated a spatial lag model with pysal. I want to know how to correctly interpret and report the resulting parameter estimates (given that spatial spillover exists). R's ...
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1answer
116 views

Point process model diagnostic: Nearest-Neighbor Distance Distribution or Pair Correlation Function?

I have a point pattern which is clearly inhomogeneous. Furthermore, the inhomogeneity has two components: a large scale effect and a local scale effect. I have constructed a Markov point process model ...
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19 views

Spatially Lagged Variable vs Spatial Lag Model

I apologies if the question is very basic. I am trying to regress X on ~ 10 I.V. The theory suggest that for a given location, X depends linearly on 9 of this I.V.. For 10th I.V., X depends on the I....
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25 views

Discrete weather data causing issue in predicting spatial yield

I want to incorporate the weather data into predicting spatial yield. Major data used: 4 years spatial yield data from a 10-ha crop field 4 years of daily weather data such as rainfall from a ...
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0answers
62 views

Spatial Lag or spatial Error Model? Deciding by using the Lagrange multiplier diagnostics

Honestly, my knowledge of geostatistics is limited. My assumptions are as follows: If I want to choose between a Spatial Lag Model (SLM) and a Spatial Error Model (SEM), I can use the Lagrange ...
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20 views

What are the techniques to predict revenue of a new shop using nearest shops?

I am trying assign a revenue for a new shop based on location. I have the data of nearest few shops. What are the techniques available to propagate/predict revenue a of new shop ?
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22 views

Correlation between 1D spatial categorical variables

I have two sets of data, representing presence/absence variables which vary along an axis (N=1e6): position, value 1, present 2, present 3, absent 4, absent .. ...
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1answer
45 views

Can Moran's I results be compared against each other in different geographies?

Background I have 50 service areas, each service area has a number of points associated with. In order to compare the areas to each other, one idea was to describe the degree to which its service ...
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1answer
44 views

How do I develop a spatial regression model when the Y and X points are partially misaligned? Do I have to use a grid?

What concept would I use to develop a spatial regression model for misaligned Insurance Claims and Policy data? For example, consider a situation where I have 1000 points that represent policies, and ...
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1answer
33 views

How can I smooth data in 2D coordinates that has time-dependent error?

I have collected some GPS data from running over and around a hill many, many times. The hill itself is about 9-10 meters high compared to the ground around it, although when I collected data, my ...
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0answers
17 views

Missing values in large spatial data

I have a groundwater dataset (4000 locations). For this data, the depth is very important to coordinate the data. I found that there are about 415 missing values in ...
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0answers
14 views

Simulation of spatial data

How to simulate spatial data assuming the spatial durbin model? Is it possible to simulate data by assigning autocorrelation values for both Y and X?

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