Adding Annotations to Objects¶
Description¶
Annotations, that is, objects of class "annotation"
, are character
vectors with all their elements named. Only one method is defined for
this subclass of character vectors, a method for show
, that shows
the annotation in a nicely formatted way. Annotations of an object can
be obtained via the function annotation(x)
and can be set via
annotation(x)<-value
.
Elements of an annotation with names "description"
and
"wording"
have a special meaning. The first kind can be obtained
and set via description(x)
and description(x)<-value
, the
second kind can be obtained via wording(x)
and
wording(x)<-value
. "description"
elements are used in way the
“variable labels” are used in SPSS and Stata. "wording"
elements of
annotation objects are meant to contain the question wording of a
questionnaire item represented by an "item"
objects. These
elements of annotations are treated in a special way in the output of
the coodbook
function.
Usage¶
annotation(x)
## S4 method for signature 'ANY'
annotation(x)
## S4 method for signature 'item'
annotation(x)
## S4 method for signature 'data.set'
annotation(x)
annotation(x)<-value
## S4 method for signature 'ANY,character'
annotation(x)<-value
## S4 method for signature 'ANY,annotation'
annotation(x)<-value
## S4 method for signature 'item,annotation'
annotation(x)<-value
## S4 method for signature 'vector,annotation'
annotation(x)<-value
description(x)
description(x)<-value
wording(x)
wording(x)<-value
## S4 method for signature 'data.set'
description(x)
## S4 method for signature 'importer'
description(x)
Arguments¶
x
an object
value
a character or annotation object
Value¶
annotation(x)
returns an object of class "annotation"
, which is
a named character. description(x)
and wording(x)
each usually
return a character string. If description(x)
is applied to a
data.set
or an importer
object, however, a character vector is
returned, which is named after the variables in the data set or the
external file.
Examples¶
vote <- sample(c(1,2,3,8,9,97,99),size=30,replace=TRUE)
labels(vote) <- c(Conservatives = 1,
Labour = 2,
"Liberal Democrats" = 3,
"Don't know" = 8,
"Answer refused" = 9,
"Not applicable" = 97,
"Not asked in survey" = 99
)
missing.values(vote) <- c(97,99)
description(vote) <- "Vote intention"
wording(vote) <- "If a general election would take place next tuesday,
the candidate of which party would you vote for?"
annotation(vote)
description:
Vote intention
wording:
If a general election would take place next tuesday, the candidate of
which party would you vote for?
annotation(vote)["Remark"] <- "This is not a real questionnaire item, of course ..."
codebook(vote)
================================================================================
vote 'Vote intention'
"If a general election would take place next tuesday, the candidate of which
party would you vote for?"
--------------------------------------------------------------------------------
Storage mode: double
Measurement: nominal
Missing values: 97, 99
Values and labels N Percent
1 'Conservatives' 2 6.7
2 'Labour' 6 20.0
3 'Liberal Democrats' 5 16.7
8 'Don't know' 2 6.7
9 'Answer refused' 1 3.3
97 M 'Not applicable' 5 16.7
99 M 'Not asked in survey' 9 30.0
Remark:
This is not a real questionnaire item, of course ...