st: Cleaning Survey Data

[Erika Kociolek <ekociole@gmail.com>]

When working with survey data - specifically closed-ended, multiple
response questions - datasets are often structured like this:

Q1_R1 Q1_R2 Q1_R3 Q1_ROTHER
1           3        98       "lemons"
2
1           2

I ultimately want to know the number of respondents that selected 1,
2, 3, 98, so I write code that looks something like this:

local values 1 2 3 98

foreach x of local values {
    generate Q1_`x'_flag = `x' if (Q1_R1 == `x' | Q1_R2 == `x' | Q1_R3 == `x')
}

Is there a better way to get to the goal (what's below)?

label define Q1_1_label "Milk"
label values Q1_1_flag Q1_1_label
label define Q1_2_label "Bread"
label values Q1_2_flag Q1_2_label
label define Q1_3_label "Apples"
label values Q1_3_flag Q1_3_label
label define Q1_98_label "Other"
label values Q1_98_flag Q1_98_label

Q1_1_flag   Q1_2_flag   Q1_3_flag   Q1_98_flag
1                                  1               1
                  1
1                1

It can be tedious to type out "if (Q1_R1 == | Q1_R2 == | Q1_R3 == |
...)" when different questions have different numbers of variables and
there are many possible responses to a given question (i.e. Q1_R1
through Q1_R17).

Thanks for any advice you have.

Best,
Erika
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