STATA 11 for Windows SAMPLE SESSION - Food Security Group ...

Stata 11 Sample Session Annex I I– Survey Instrument
Command Description
assert assert verifies that an expression is true. if it is, the command
produces no output; if it is not, assert informs you that the
"assertion is false".
append using append appends a STATA-format dataset stored on disk to the
mvencode varlist, mv (#),
[override]
end of the dataset in memory.
changes all occurrences of missing to # in the variable listing
specified.
override specifies the protection provided by mvencode is to be
overridden. without this option, mvencode refuses to make the
requested change if # is already used in the data.
mvdecode varlist, mv (#) changes all occurrences of # to missing in the variable list
egen
creates a new variable equal to the specified functions and its
arguments
regress depvar varlist regress estimates a model of the dependent variable on variables
in varlist
xi: regress ....i.variable constructs categorical dummy variables for variables omitting
the first category.
predict variable stores the predicted values from the regression in variable. what
this command can do is determined by the previous command.
probit probit estimates maximum-likelihood probit models.
search searches the keyword database. Use search when you are not
certain of the command, e.g., search string shows all commands
associated with strings.
tables calculates and displays tables of statistics.
reshape converts data from wide to long form and vice versa. ‘wide’ and
‘long’ refer to how data are organized. See reshape notes
below.
fillin varlist adds observations with missing data so that all combinations of
varlist exist, thus rectangularizing the file. the variable _fillin is
added to the data. _fillin is 1 for created observations and
0 for previously existing observations.
(svy commands) these are commands prefixed with ‘svy’ and they pertain to
commands used in analyzing survey data.
tables calculates and displays tables of statistics.
format varlist %fmt formats numeric variables as follows--number before the
decimal indicates the length of the variable, number after the
decimal indicates number of decimal places:
%#.#g - general numeric format (%5.0g)
%#.#f - fixed numeric format (e.g., %5.2f)
%#.#e -base 10 power
strings are formatted as follows and can be 81 chars long:
%#s (e.g., %10s)
Reshape notes: The reshape command is particularly useful for files such as that shown in the following
example:
Households were asked about the number of livestock owned for three types of livestock coded 330, 331
and 335. To save on data entry time, only those entries reporting any livestock were entered. Missing
livestock codes in the file therefore means that the household did not own the livestock associated with
the code. The file looks like this.
115