Measurements of subcutaneous and visceral fat

Source: R/MethComp-package.R

43 persons had Subcutaneous and Visceral fat thickness measured at Steno Diabetes Center in 2006 by two observers; all measurements were done three times. The interest is to compare the measurements by the two observers. Persons are items, observers are methods, the three replicates are exchangeable within (person,observer)=(item,method)

Format

A data frame with 258 observations on the following 6 variables.

Id

Person id.

Obs

Observers, a factor with levels KL and SL.

Rep

Replicate — exchangeable within person and observer.

Sub

Subcutaneous fat measured in cm.

Vic

Visceral fat measured in cm.

Examples


data(fat)
str(fat)
#> 'data.frame':	258 obs. of  5 variables:
#>  $ Id : num  1 1 1 3 3 3 5 5 5 11 ...
#>  $ Obs: Factor w/ 2 levels "KL","SL": 1 1 1 1 1 1 1 1 1 1 ...
#>  $ Rep: num  1 2 3 1 2 3 1 2 3 1 ...
#>  $ Sub: num  1.6 1.7 1.7 2.8 2.9 2.8 2.7 2.8 2.9 3.9 ...
#>  $ Vic: num  4.5 4.4 4.7 6.4 6.2 6.5 3.6 3.9 4 4.3 ...
vic <- Meth( fat, meth=2, item=1, repl="Rep", y="Vic" )
#> The following variables from the dataframe
#> "fat" are used as the Meth variables:
#> meth: Obs 
#> item: Id 
#> repl: Rep 
#>    y: Vic 
#>        #Replicates
#> Method          3 #Items #Obs: 258 Values:  min med max
#>     KL         43     43       129          2.0 3.9 6.5
#>     SL         43     43       129          2.3 4.1 6.7
str(vic)
#> Classes ‘Meth’ and 'data.frame':	258 obs. of  5 variables:
#>  $ meth: Factor w/ 2 levels "KL","SL": 1 1 1 1 1 1 1 1 1 1 ...
#>  $ item: Factor w/ 43 levels "1","2","3","4",..: 1 1 1 3 3 3 5 5 5 11 ...
#>  $ repl: Factor w/ 3 levels "1","2","3": 1 2 3 1 2 3 1 2 3 1 ...
#>  $ y   : num  4.5 4.4 4.7 6.4 6.2 6.5 3.6 3.9 4 4.3 ...
#>  $ Sub : num  1.6 1.7 1.7 2.8 2.9 2.8 2.7 2.8 2.9 3.9 ...
BA.est( vic, linked=FALSE )
#> Error in solve.default(do.call("cbind", Xcols), apply(shifted, 2, fun,     ...)): Lapack routine dgesv: system is exactly singular: U[9,9] = 0