Purpose
Defines and modifies a reference vector for life table computations using the SCURV command in PEANUTS or for calculating risk function estimates in GMBO, PECAN or AMFIT using the RISK command.
Syntax
REFVECTOR { record# | 0 | {SHOW { vlist } | CLEAR } @
REFMODIFY transformation_str @
Arguments and Subcommands
record#
Defines record# as the reference covariate vector. This makes a copy of the data in the indicated record.
0
Defines the reference covariate vector to be the zero vector.
SHOW vlist
Displays reference vector covariate values for the listed variables.
REFMODIFY transformation_str
Carries out the indicated transformations on the reference vector. If the vector does not exist, it will be created and initialized to 0 before the transformations. Several transformations can be specified in one statement, and these should be separated by semicolons (;).
REFVECTOR @
Displays the values of all data in the reference vector.
Remarks
Once a reference vector has been created, ordinary transformations as well as TTRAN or ITRAN transformations are applied to both the data and the reference vector. The MODIFY subcommand is used to transform only the values in the reference vector and does not affect the data used for fitting models.
Giving this command with no arguments results in a list of the values of all covariates in the reference vector.
The REFVECTOR command is used in the following PEANUTS examples: V2FEAT.PNT, and MLUNG.PNT; it is also used in the AMFIT example PROFILE.AMF.
Examples
a) Designate record 10 as the reference vector
REFVECTOR 10 @
b) Define the value of the variable age in the current reference vector to be 30, agex to be 5, and dose to be 0.75.
REFMODIFY age = 30 ; agex = 5 ;
dose = 0.75 @
c) Display the reference vector values for age, agex, and dose
REFVECTOR SHOW age agex dose @
d) Set the reference vector to be the 0 vector.
REFVECTOR 0 @
e) Specify a reference vector, modify one of its values, and plot the relative risk function.
REFECTOR
10@
REFMODIFY time=250 @
SCURV
RR @