Questions tagged [gis]

Geographic information systems (GIS) provide facilities for storing, managing and analyzing geographic data which can be used for statistical purposes.

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20 views

After predicting a Random Forest how do I spatially project predictions onto a raster?

After making a random forest model of nitrate prediction from a set of 11 (categorical and continuous) explanatory variables I want to visualize these projections spatially on a map. Most of the ...
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18 views

Measure "dispersion" of geospatial data

I have a dataframe of lat and longs (of postal codes of Canada), let's say they look something like this. I'd like to come up with a measure of dispersion - basically how spread out these postal ...
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1answer
18 views

reflectance value ranges from -3.40282e38 to 3.40282e38 in qgis [closed]

reflectance value ranges from -3.40282e38 to 3.40282e38 in qgis atmoshpherically corrected image, I want my value to range between 0-1 how can i fix this?
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35 views

Creating a colour gradient for a set of data points from scratch

I'm struggling to even figure out where to post this as I realise it is an odd problem, so hopefully someone with expertise in data visualisation can help me. The fundamentals of my code work, but I ...
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19 views

Do I correctly apply hierarchical clustering and K-means on the resource-selection-function values?

I'm trying to find the best way to classify bivariate point patterns in spatstat according to the relationship between two point species: Point pattern ...
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18 views

Point pattern classification with spatstat: how to choose the right bandwidth for the kernel density?

I'm trying to find the best way to classify bivariate point patterns in spatstat according to the relationship between two point species: Point pattern ...
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0answers
18 views

How to use a temperature raster (e.g., PRISM) to constrain temperature values in a thin plate spline regression and interpolation

I have point data with temperature, latitude, longitude, and elevation. I am interpolating across space to the extent of those points, and have been using elevation as a covariate in the ...
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11 views

spatial correlation between two hexa/density maps

I was working on a report and was faced with a question regarding maps and spatial analysis. I want to compare some maps and find the similarities/differences among them. The maps represent the sum of ...
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1answer
10 views

In the R package spANOVA can coordinates be entered directly as Lat/Longs or is a map projection required?

I have some data on fish abundance in a harbour in Canada that I'm analyzing using the R package spANOVA (Spatial ANOVA). I'm using the function aovSAR.gen which takes the arguments: aovSar.gen(...
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52 views

Model evaluation from a comparison between simulated density data and individual presence data

I built a mathematical model of range expansion for a mosquito species. The model output is a map (raster format) of simulated mosquito density (mosquitoes/km²) in a study area. Here is an overview ...
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25 views

Performing Paired Sample t-test on sampled height measurements when using different platform sensors?

I’ll be upfront, my Achilles’ heel is understanding how to apply statistics. I want to test/compare the relative accuracy of sampled height points created at set intervals (say 50 metres) along a 1 ...
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73 views

Variogram fit in R not converging

I have taken a shapefile from Open NYC Data and performed the following method. My end goal is to predict Taxi trip_duration at various points across the city of ...
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1answer
29 views

How do I study the association between categorical rasterised environmental variables in R?

I would like to study the association between categorical rasterised environmental variables in R. Is there any way to do it in R?
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1answer
151 views

Predict crowded areas based on time series data points of latitude and longitude

I have time series location data (latitude/longitude) from users who send their location every minute. Basically the history of different users moving on a map. ...
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1answer
16 views

What factors need to be considered to decide the radius of a bubble map or is there a generic formula?

I recently started with GIS and I am learning as I go about implementing things. Take the case of JHU Dashboard or the first world map in this NYT article or the maps in this Guardian article, what I ...
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256 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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2answers
673 views

How to create training data for CNN using remote sensing imagery

Before I start with the issue I would like to touch base with some background information. I had been working with Random Forest for classification of Remote Sensing data, here the classification ...
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1answer
282 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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97 views

How to handle multiple points at the same location in spatial interpolation?

I am new to the topic of spatial interpolation and would appreciate your opinion on a general question which has arisen. Suppose I have a data set containing rental rates for different apartments in ...
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1answer
29 views

How to get the density estimate for the whole region based on data from several locations?

I am collecting air pollutant data for every area in a region. The available data I can find only has the data from stations in a few areas. Is it possible to estimate the air pollutant density for ...
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38 views

Confidence interval of the weighted mean

In a sampling survey, I get $N$ cases about whether to support a policy and get $x_i(i=1,2,..,N)$, $x_i$ is binary, support $x_i=1$, and $x_i=0$ otherwise, give a weight $w_i(i=1,2,..,N)$to every case,...
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0answers
64 views

Find the nearest point of interest by latitude and longitude

I have lat/long value of 180k points of interests. Now I have lat/long value of about 800k locations, what is the most efficient way to find the nearest points of interests for each of these 800k ...
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1answer
470 views

Clustering spatial data based on location and values

I'm looking for a way, preferably in R, to create a cluster of point data (specifically, the centroids of UK postcodes), where each cluster comes as close as possible to containing a certain number of ...
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110 views

Rate Smoothing in Spatial Data -

I asked this question on Reddit a few days ago but didn't get any responses. Working on some spatial epidemiology research a while back, that has resurfaced, I was told that I should smooth the ...
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1answer
174 views

Satellite data pre-processing for Keras CNNs [closed]

I’m looking at satellite data and want to do object detection using CNNs in Keras. I’m currently pre-processing the data (turning them into tensors) that I’ve obtained which include the original ...
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100 views

Basics of Akaike's Information Criterion in GIS/Hydrology

I have been asked to use the AIC to assess the relative fitness of various terrain wetness index (TWI) methods for predicting soil moisture in a specific study site. The TWI is calculated from a ...
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3answers
202 views

How do I calculate the proportion of smaller squares covered by a larger circle?

I would like to determine the proportion covered by the circle (say r = 2800m) of each cell (say 1000 x 1000 m). The circle is centered around the center of the focal cell of a rectangular ...
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1answer
47 views

Given a set of addresses, pick a geographically even subset for sampling

There are a certain number of houses spread randomly across a city. We have addresses and GPS coordinates for each house. How can we select a geographically representative, fixed-size sample out of ...
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2answers
1k views

What statistical model or algorithm could be used to solve the John Snow Cholera problem?

I'm interested in learning how to develop a geographic approximation of some kind of epicenter based on the data from the John Snow Cholera outbreak. What statistical modeling could be used to solve ...
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1answer
190 views

Metric for spatial auto cross correlation?

I am trying to find anomalies in time series data with geolocations. For different time intervals, e.g. for some week or for some day or for 6 consecutive months, I want to learn whether there is ...
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1answer
37 views

Population Modeling Statistics on a Map

I've got a question regarding the modeling of populations. So I am programming a population map that is geometrically amendable. For this, one can define an area and define the number of people ...
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0answers
36 views

Sample class ratio vs. real world class ratio

I am using RandomForest to generate a model to detect burned forest areas based on the reflectance values of satellite imagery. The burned area accounts, on average, for 10% of the pixels in my images,...
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0answers
158 views

Input geolocation Data in Neural Network

I am working on a Neural Network that should predict certain transport-tariffs based on start and end region of the transport. The region can take different forms, from a whole country to a range of ...
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1k views

Performing spatial logistic regression in R

I am trying to perform a logistic regression with the following code Y ~ x1+x2+x3,data=data, family=binomial(link="logit"). However on inspection of both the ...
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1answer
9k views

Applying DBSCAN to a huge GIS dataset with a Haversine distance metric.

I have a training set (2GB) that contains GIS trajectory data for multiple taxi rides. I want to cluster the final destinations based on their spatial density and have therefore been trying to use the ...
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2answers
6k views

The right way to use Machine Learning to predict latitude and longitude

There are some simple ML techniques that can be used to easily predict latitude/longitude co-ordinates, such as predicting the latitude and longitude separately using two different models. However, I ...
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0answers
20 views

What is the best method to statistically test two areas?

I am investigating the difference in childhood obesity rates between Dudley and Brighton & Hove. These areas have similar deprivation rates but very different childhood obesity rates. I am looking ...
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1answer
2k views

Predicting Co-Ordinate Data

This is on a prediction model we were trying out among a bunch of us trying out ML for the first time. Basically I have a training data set of network user ID's with their location (latitude and ...
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0answers
75 views

Help required in controlling for socioeconomic factors when mapping travel behavior

Background I have cleaned disaggregate travel data down to a household level (of about 75% of households) and socio economic data aggregated into 100-200 household blocks. What I'm wanting to do is ...
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2answers
711 views

How to create a GIS basemap in R? [closed]

I am an expert GIS user moving towards R more and more. I have been using R for some basic regressions and such, but I would like to begin to use and manipulate GIS data in R. How can I create a ...
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0answers
57 views

Correcting for Bias due to Larger Populations

I'm mining social networks point data to use with GIS (Geographic information system). Obviously there are going to be more posts in areas with higher population which, if uncorrected, would end up ...
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2answers
655 views

How to predict demand from historical "continuous" event data (date, lat, lon)?

I am attempting to predict demand for our service, both quantity but maybe more important, location (hotspots). I am by no means an experienced statistician, so I need some help :) I have all the ...
5
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1answer
291 views

Testing for non-random overlap of polygons

I have two polygon shapefiles and I want to see to what extent the observed amount of overlap is due to chance. I'm thinking of some kind of permutation test, but not sure of the best way to proceed....
3
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1answer
673 views

Clustering spatio-temporal data?

I have data in the form of timestamp,lat,long which is gps data for users. I'm new to data mining and want to understand how can I start clustering these data to understand more about it. Should I ...
5
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0answers
125 views

Help with designing the analysis of a radio telemetry study

I was wondering if there are any spatial ecologists out there who can provide some insight on the trouble I'm having with my Masters research. I am looking at the association a bat species to high ...
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3answers
2k views

95% confidence ellipse of Lenth's maximum likelihood estimation

I'm attempting to write a simple mobile app to help colleagues triangulate the signal of transmitter-fitted animals in the field. I've been using Russell Lenth's 1981 method of Maximum Likelihood ...
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2answers
259 views

How to capture competitive spatial interactions between multiple stores and customers

I am estimating sales with data on customer and store locations and attributes using a Huff-style model, where sales decay with drive time and increase with attractiveness of the store. One ...
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1answer
211 views

Identifying culs-de-sac (circular housing arrangements) with GIS data

I'm thinking about a new project, so I don't have data yet, but I plan on collecting GIS information for houses within a state. Usually in the U.S., these dead-end streets will have a large circle ...