mesa.model: Example of a 'STmodel' structure

Description Format Details Source References See Also Examples

Description

Example of a model structure holding observations, geographic covariates, observation locations, smooth temporal trends, spatio-temporal covariates, and covariance specifications for the model.

Format

A list with elements, a detailed description of each elements is given in details below

Details

A STmodel object consists of a list with, some or all of, the following elements:

obs

A data.frame with columns:

obs

The value of each observation.

date

The observations time, preferably of class Date.

ID

A character-class giving observation locations; should match elements in locations$ID.

idx

match between obs$ID and locations$ID for faster computations.

The data.frame is sorted by date and idx.

locations.list,locations

Specification of locations and data.frame with locations for observations (and predictions), see processLocation.

D.nu,D.beta

Distance matrices for the locations in the, possibly different coordinate systems for beta- and nu-fields. See processLocation.

cov.beta,cov.nu

Covariance structure for beta- and nu-fields, see updateCovf.

LUR.list,LUR

Specification of covariates for the beta-fields and a list with covariates for each of the beta-fields, see processLUR and createLUR.

trend,trend.fnc

The temporal trends with one of the columns being named date, preferably of class Date providing the time alignment for the temporal trends.

F

A matrix contaning smooth temporal trends for each observation; elements taken from trend.

ST.list,ST,ST.all

Spatio-termporal covariates, NULL if no covariates. For the observations and all space-time locations respectively, see processST and createST.

old.trend,fit.trend

Additional components added if the observations have been detrended, see detrendSTdata.

Source

Contains monitoring data from the MESA Air project, see Cohen et.al. (2009) and mesa.data.raw for details.

References

M. A. Cohen, S. D. Adar, R. W. Allen, E. Avol, C. L. Curl, T. Gould, D. Hardie, A. Ho, P. Kinney, T. V. Larson, P. D. Sampson, L. Sheppard, K. D. Stukovsky, S. S. Swan, L. S. Liu, J. D. Kaufman. (2009) Approach to Estimating Participant Pollutant Exposures in the Multi-Ethnic Study of Atherosclerosis and Air Pollution (MESA Air). Environmental Science & Technology: 43(13), 4687-4693.

See Also

createSTmodel for creation of STmodel objects.
createSTdata for creation of the originating STdata object.

Other example data: MCMC.mesa.model, est.cv.mesa, est.mesa.model, mesa.data.raw, pred.mesa.model

Examples

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##load the data
data(mesa.model)

##examine components
names(mesa.model)
print(mesa.model)
summary(mesa.model)

##requested geographic and spatio-temporal covariates
mesa.model$LUR.list
mesa.model$ST.list

##covariates for the temporal intercept
head(mesa.model$LUR$const)
##...and the two smooth temporal trends
head(mesa.model$LUR$V1)
head(mesa.model$LUR$V2)

##Some important dimensions of the model
loglikeSTdim(mesa.model)

Example output

Loading required package: Matrix
 [1] "obs"            "trend"          "trend.fnc"      "locations.list"
 [5] "locations"      "cov.beta"       "cov.nu"         "LUR.list"      
 [9] "ST.list"        "LUR.all"        "LUR"            "ST.all"        
[13] "ST"             "F"              "D.nu"           "D.beta"        
[17] "nt"            
STmodel-object with:
	No. locations: 25 (observed: 25)
	No. time points: 280 (observed: 280)
	No. obs: 4577

Trend with 2 basis function(s):
[1] "V1" "V2"
with dates:
	1999-01-13 to 2009-09-23

Models for the beta-fields are:
$const
~log10.m.to.a1 + s2000.pop.div.10000 + km.to.coast

$V1
~km.to.coast

$V2
~km.to.coast

1 spatio-temporal covariate(s):
[1] "lax.conc.1500"

Covariance model for the beta-field(s):
	Covariance type(s): exp, exp, exp 
	Nugget: No, No, No 
Covariance model for the nu-field(s):
	Covariance type: exp 
	Nugget: ~type 
	Random effect: No 
All sites:
  AQS FIXED 
   20     5 
Observed:
  AQS FIXED 
   20     5 

For AQS:
  Number of obs: 4178
  Dates: 1999-01-13 to 2009-09-23
For FIXED:
  Number of obs: 399
  Dates: 2005-12-07 to 2009-07-01
Summary of observations:
      obs             date           
 Min.   :0.678   Min.   :1999-01-13  
 1st Qu.:3.330   1st Qu.:2001-11-28  
 Median :3.786   Median :2004-09-15  
 Mean   :3.774   Mean   :2004-08-11  
 3rd Qu.:4.269   3rd Qu.:2007-05-23  
 Max.   :5.752   Max.   :2009-09-23  

Summary of locations:
      ID                  x                y            x.beta      
 Length:25          Min.   :-10918   Min.   :3742   Min.   :-10918  
 Class :character   1st Qu.:-10898   1st Qu.:3770   1st Qu.:-10898  
 Mode  :character   Median :-10888   Median :3780   Median :-10888  
                    Mean   :-10884   Mean   :3778   Mean   :-10884  
                    3rd Qu.:-10864   3rd Qu.:3786   3rd Qu.:-10864  
                    Max.   :-10846   Max.   :3801   Max.   :-10846  
     y.beta          x.nu             y.nu           long       
 Min.   :3742   Min.   :-10918   Min.   :3742   Min.   :-118.5  
 1st Qu.:3770   1st Qu.:-10898   1st Qu.:3770   1st Qu.:-118.3  
 Median :3780   Median :-10888   Median :3780   Median :-118.2  
 Mean   :3778   Mean   :-10884   Mean   :3778   Mean   :-118.2  
 3rd Qu.:3786   3rd Qu.:-10864   3rd Qu.:3786   3rd Qu.:-118.0  
 Max.   :3801   Max.   :-10846   Max.   :3801   Max.   :-117.8  
      lat           type   
 Min.   :33.67   AQS  :20  
 1st Qu.:33.93   FIXED: 5  
 Median :34.01             
 Mean   :33.99             
 3rd Qu.:34.07             
 Max.   :34.20             

Summary of geographic covariates:
$const
  (Intercept) log10.m.to.a1   s2000.pop.div.10000  km.to.coast    
 Min.   :1    Min.   :1.825   Min.   :1.555       Min.   : 1.023  
 1st Qu.:1    1st Qu.:2.614   1st Qu.:2.785       1st Qu.: 5.948  
 Median :1    Median :2.862   Median :4.106       Median :15.000  
 Mean   :1    Mean   :2.864   Mean   :4.245       Mean   :11.432  
 3rd Qu.:1    3rd Qu.:3.224   3rd Qu.:5.219       3rd Qu.:15.000  
 Max.   :1    Max.   :3.812   Max.   :8.206       Max.   :15.000  

$V1
  (Intercept)  km.to.coast    
 Min.   :1    Min.   : 1.023  
 1st Qu.:1    1st Qu.: 5.948  
 Median :1    Median :15.000  
 Mean   :1    Mean   :11.432  
 3rd Qu.:1    3rd Qu.:15.000  
 Max.   :1    Max.   :15.000  

$V2
  (Intercept)  km.to.coast    
 Min.   :1    Min.   : 1.023  
 1st Qu.:1    1st Qu.: 5.948  
 Median :1    Median :15.000  
 Mean   :1    Mean   :11.432  
 3rd Qu.:1    3rd Qu.:15.000  
 Max.   :1    Max.   :15.000  


Summary of smooth trends:
       V1                V2                date           
 Min.   :-2.0807   Min.   :-2.27852   Min.   :1999-01-13  
 1st Qu.:-0.8828   1st Qu.:-0.72370   1st Qu.:2001-09-15  
 Median : 0.1345   Median :-0.01471   Median :2004-05-19  
 Mean   : 0.0000   Mean   : 0.00000   Mean   :2004-05-19  
 3rd Qu.: 0.8756   3rd Qu.: 0.73483   3rd Qu.:2007-01-20  
 Max.   : 1.8503   Max.   : 2.08859   Max.   :2009-09-23  

Summary of spatio-temporal covariates.
 lax.conc.1500     
 Min.   : 0.00000  
 1st Qu.: 0.09528  
 Median : 1.81705  
 Mean   : 3.47925  
 3rd Qu.: 5.12175  
 Max.   :34.00420  

Summary for observations of type AQS 
      obs              date           
 Min.   :0.8102   Min.   :1999-01-13  
 1st Qu.:3.3406   1st Qu.:2001-09-19  
 Median :3.7916   Median :2004-03-17  
 Mean   :3.7836   Mean   :2004-04-22  
 3rd Qu.:4.2751   3rd Qu.:2006-12-30  
 Max.   :5.7516   Max.   :2009-09-23  

Summary for observations of type FIXED 
      obs             date           
 Min.   :0.678   Min.   :2005-12-07  
 1st Qu.:3.217   1st Qu.:2006-12-06  
 Median :3.755   Median :2007-10-10  
 Mean   :3.669   Mean   :2007-10-28  
 3rd Qu.:4.196   3rd Qu.:2008-08-27  
 Max.   :5.285   Max.   :2009-07-01  
$const
~log10.m.to.a1 + s2000.pop.div.10000 + km.to.coast

$V1
~km.to.coast

$V2
~km.to.coast

[1] "lax.conc.1500"
         (Intercept) log10.m.to.a1 s2000.pop.div.10000 km.to.coast
60370002           1      2.861509            1.733283   15.000000
60370016           1      3.461672            1.645386   15.000000
60370030           1      2.561133            6.192630   15.000000
60370031           1      3.111413            2.088930    1.023311
60370113           1      2.762193            7.143731    6.011075
60371002           1      2.760931            4.766780   15.000000
         (Intercept) km.to.coast
60370002           1   15.000000
60370016           1   15.000000
60370030           1   15.000000
60370031           1    1.023311
60370113           1    6.011075
60371002           1   15.000000
         (Intercept) km.to.coast
60370002           1   15.000000
60370016           1   15.000000
60370030           1   15.000000
60370031           1    1.023311
60370113           1    6.011075
60371002           1   15.000000
$T
[1] 280

$m
[1] 3

$n
[1] 25

$n.obs
[1] 25

$p
const    V1    V2 
    4     2     2 

$L
[1] 1

$npars.beta.covf
exp exp exp 
  2   2   2 

$npars.beta.tot
exp exp exp 
  2   2   2 

$npars.nu.covf
[1] 2

$npars.nu.tot
[1] 4

$nparam.cov
[1] 10

$nparam
[1] 19

SpatioTemporal documentation built on May 2, 2019, 8:49 a.m.