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

Stata 11 Sample Session Section 2 – Restructuring Data Files – Table Lookup & Aggregation
Exercise 2.1 Produce similar output using calories retained
(production minus sales) instead of calories produced. It
will show calories retained per adult equivalent per day
from the total of the same six food crops. The output
should be broken down by district and calories retained
quartile.
Hints:
a. The procedure is very similar to the work that we
just completed. Open a new do-file to save your
commands for this exercise.
b. Sales come from c-q5.dta.
c. Check the file for the appropriate variable for the
quantity of sold production. Note that the product
codes are the same as for c-q4.dta. Also check for
the variables by which to sort.
d. You can start from a blank file and build all the
commands necessary to produce the calories
retained, or you can copy the commands used to
generate the table from section 2 and adjust the
commands as necessary to calculate the calories
retained. Changes must be made for file names and
variables.
e. Computing the calories sold involves the same
basic steps as computing the calories produced.
(Step 1). Average calories sold should be
1,407,493
f. Merge this newly created file, (the file containing
calories sold), with the file containing calories
produced, hh-file3.dta. Check the _merge variable
(tab _merge) and explain why you see a value of
(2) and a value of (3).
g. Keep in mind that only 257 households sold
products, but all 343 households produced and
retained calories. If the “calories sold” variable is
missing, it means the household did not sell food,
so it should be recoded to zero.
h. Compute calories retained = calories produced -
calories sold. The average calories retained per
adult equivalent for the whole population should be
3044.261
i. Rank into quartiles.
j. Use the Tabulate command to show calories
retained by district and quartile.
k. Save the data file to the name, hh-file4.dta.
l. Save the contents of the do-file editor to a new
name reflecting the name of the exercise.
Below is an example of the output you should produce:
86