st: Advice on content of a do file

[Peter King <kingsocres@gmail.com>]

Hi All,

I'm preparing to analyse survey responses to the ICECAP-A questionnaire. 
The ICECAP-A developers have provided code to substitute into a Stata do 
file to allow the calculation of values or tariffs for each respondent.

The code is as follows:

matrix UTILS=(-0.001,0.101,0.191,0.222\/*

*/-0.024,0.096,0.189,0.228\/*

*/0.006, 0.084, 0.156, 0.188\/*

*/0.021, 0.091, 0.159, 0.181\ /*

*/ -0.003, 0.069, 0.154, 0.181)

gen sta_index=UTILS[1,stability[_n]]

gen att_index=UTILS[2,attachment[_n]]

gen aut_index=UTILS[3,autonomy[_n]]

gen ach_index=UTILS[4,achievement[_n]]

gen enj_index=UTILS[5,enjoyment[_n]]

gen tariff=sta_index+att_index+aut_index+ach_index+enj_index


I have formatted my data as specified below:

"This code, when substituted into a Stata do file, will allow 
calculation of ICECAP-A tariffs for each respondent in a study, based on 
their answers to the five classification questions. Statistical analyses 
can then be conducted on these tariffs. Indeed they can be conducted on 
the five index values also, to ascertain sensitivity of these to 
differences in factors.


"Data should be set up with one study participant per row. As specified 
on the ICECAP-A questionnaire, coding should be such that the 'top' 
level (full capability for an attribute) should take the value '4', down 
to the bottom level (no capability) which should take the value '1'. NB 
this coding is the opposite of that used in instruments such as the 
EQ-5D (where 1 is top level). The five variables, containing a 
respondent's five ICECAP-A responses should be named stability, 
attachment, autonomy, achievement, enjoyment."

When I run the do file with the specified content I get the following 
reply/output:

. do "C:\Documents and Settings\User\My Documents\FCSPRU Files\Current 
projects\BIS 2006\Surve
> ys\Postal survey\Wave 2 2012\ICECAP Tariff.do"

. matrix UTILS=(-0.001,0.101,0.191,0.222\/*
> */-0.024,0.096,0.189,0.228\/*
> */0.006, 0.084, 0.156, 0.188\/*
> */0.021, 0.091, 0.159, 0.181\ /*
> */ -0.003, 0.069, 0.154, 0.181)

. gen sta_index=UTILS[1,stability[_n]]
matrix operators that return matrices not allowed in this context
r(509);

end of do-file

r(509);

.
I am new to using do files and wonder whether I should be including 
other information in the do file?  Or is something else wrong in the code?

Any suggestions from more experienced users will be greatlt appreciated.


Many thanks,

Peter King
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