RASCH MODEL AN ENVIRONMETRIC TOOL

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RASCH MODEL AN ENVIRONMETRIC TOOL
MEASUREMENT FOR MAP POLLUTION
PEDRO ÁLVAREZ
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RANKING OF LOCATIONS ACCORDING TO THEIR LEVEL OF
ATMOSPHERIC POLLUTION
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RASCH FORMULATION
CONSTRUCT ATMOSPHERIC POLLUTION Xni
Pollutants di
Locations ßn
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REPRESENTATION OF THE LATENT VARIABLE AS A
STRAIGHT LINE ßn is the location n
di is the pollutant i
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ATMOSPHERIC POLLUTION AS A COMMUN REFERENCE
FRAMEWORK FOR POLLUTANTS
Pollutants CO, SO2, NO, NO2 noise
Pollutants were measured in 60 different
locations (sample points) with a mobil monitoring
unit
Transforming non categorical data into selected
category
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(No Transcript)
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POLLUTANTS IN MEASUREMENT ORDER
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Locations measures
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APPLYING GEOGRAPHICAL INFORMATION SYSTEMS (GIS),
KRIGING INTERPOLATION TECHNICS
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POLLUTION MAP
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Map of reliable (kriging standard deviation, KSD,
below 6.5) and unreliable (kriging standard
deviation, KSD, above 6.5) estimates of
atmospheric pollution.
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Probability map of atmospheric pollution gt 52
(Rasch measure) in the center of Badajoz. Circles
represent sample points.