Merits of two instruments designed to measure certain aspects of human lung function (Vital Capacity)

Measurement on certain aspects of human lung capacity for 72 patients on 4 instrument-operative combination, i.e. two different instruments and two different users, a skilled one and a new one.

Format

A data frame with 288 observations on the following 5 variables.

meth: a factor with levels StNew, StSkil, ExpNew and ExpSkil, representing the instrument by user combinations. See below.
item: a numeric vector, the person ID, i.e. the 72 patients
y: a numeric vector, the measurements, i.e. vital capacity.
user: a factor with levels New Skil, for the new user and the skilled user
instrument: a factor with levels Exp and St, for the experimental instrument and the standard one.

Source

V. D. Barnett, Simultaneous Pairwise Linear Structural Relationships, Biometrics, Mar. 1969, Vol. 25, No. 1, pp. 129-142.

Examples


data(VitCap)
Vcap <- Meth( VitCap )
#> The following variables from the dataframe
#> "VitCap" are used as the Meth variables:
#> meth: meth 
#> item: item  
#>    y: y 
#>           #Replicates
#> Method             1 #Items #Obs: 288 Values:  min  med  max
#>   StNew           72     72        72          960 1985 4180
#>   StSkil          72     72        72          920 2125 4040
#>   ExpNew          72     72        72          600 1945 3960
#>   ExpSkil         72     72        72          640 1940 4150
str( Vcap )
#> Classes ‘Meth’ and 'data.frame':	288 obs. of  6 variables:
#>  $ meth      : Factor w/ 4 levels "StNew","StSkil",..: 2 2 2 2 2 2 2 2 2 2 ...
#>  $ item      : Factor w/ 72 levels "1","2","3","4",..: 1 2 3 4 5 6 7 8 9 10 ...
#>  $ repl      : Factor w/ 1 level "1": 1 1 1 1 1 1 1 1 1 1 ...
#>  $ y         : num  3450 1310 3820 2110 1860 1940 2360 2880 1980 3120 ...
#>  $ user      : Factor w/ 2 levels "New","Skil": 2 2 2 2 2 2 2 2 2 2 ...
#>  $ instrument: Factor w/ 2 levels "Exp","St": 2 2 2 2 2 2 2 2 2 2 ...
plot( Vcap )