The observed function is the first function in the vpc piping chain and is used for specifying observed data and variables for VPC. Note: Observed data must not contain missing DV and may require filtering MDV == 0 before generating VPC.

observed(o, ...)

# S3 method for data.frame
observed(
o,
x,
yobs,
pred = NULL,
blq = NULL,
lloq = -Inf,
alq = NULL,
uloq = Inf,
...
)

## Arguments

o

A data.frame of observation data.

...

Other arguments.

x

Numeric x-variable, typically named TIME.

yobs

Numeric y-variable, typically named DV.

pred

Population prediction variable, typically named PRED.

blq

Logical variable indicating below limit of quantification.

lloq

Number or numeric variable in data indicating the lower limit of quantification.

alq

Logical variable indicating above limit of quantification .

uloq

Number or numeric variable in data indicating the upper limit of quantification.

## Value

A tidyvpcobj containing both original data and observed data formatted with x and y variables as specified in function. Resulting data is of class data.frame and data.table.

simulated censoring stratify predcorrect binning binless vpcstats