Chapter One Spatial Analysis Patterns of spatially distributed points Correlation with environmental variables Interpolations and predictive models Spatial autocorrelation gt spatial patterns aggregation Based on distance to neighbors KaplanMeier estimator Morans I ID: 408119
Download Presentation The PPT/PDF document "Spatial Analysis" is the property of its rightful owner. Permission is granted to download and print the materials on this web site for personal, non-commercial use only, and to display it on your personal computer provided you do not modify the materials and that you retain all copyright notices contained in the materials. By downloading content from our website, you accept the terms of this agreement.
Slide1
Spatial Analysis
Chapter OneSlide2
Spatial Analysis
Patterns of spatially distributed points.
Correlation with environmental variables.
Interpolations and predictive models.Slide3
Spatial autocorrelation -> spatial patterns, aggregation. Based on distance to neighbors. Kaplan-Meier estimator, Moran’s I.
Spatial Interpolation -> estimate variables in unknown locations based on known locations.
Krigging
.
Spatial Regression -> regression analysis considering spatial relationships.Slide4
Spatial Interaction -> Gravity models. Spatially explicit interactions. Movement patterns, people movement, vehicle traffic. Fish schools and bird flocks. Game theory.
Simulations.Slide5Slide6Slide7
Why do we care about this???
Analyzing distributions and factors shaping them.
Predicting locations.
Relative influence of factors in distributions.
Variation in pressure to understand selection and evolution.Slide8
Today…
Generate random points in a plot, using Poisson Distribution.
Analyze the aggregation pattern of points using the Kaplan-Meier Estimator.
Use a
Chagas
’ Disease data set.Slide9
Poisson Distribution
Discrete probability distribution.
Rare events.
Use in spatial analysis is a generalization, based on
λ
-> “intensity” of event occurrence.Slide10
Kaplan-Meier Estimator
Estimation of distance distribution.
Calculation of
G(r
) random distribution of nearest neighbor distance in a given space.
Compare the observed distribution with the random
G(r
)Slide11
The Data Set
Chagas
Disease vectors Spatial Distribution -> Maria Victoria Suarez (PUCE).
Look for the relationship between human settlements and spatial distribution of
Chagas
disease vectors in the surrounding natural areas.Slide12
Chagas Disease
Tropical Disease caused by
Trypanosoma
cruzi
Vector ->
Triatomine
hemipterans
.
Chronic disease. Lethal causing liver and/or heart failureSlide13
Methodology
Random sampling of nests and palm trees in a 600x600m plot, adjacent to a human settlement in natural or semi-natural habitat.
Compare the distribution of positive points, with the random expected distribution using
G(r
)