Multiplying observations in a variable list

[Mari Verulashvili]

In a dataset of multiple variable lists, I would like to multiply the value of only selected variables in one variable list by 4. Namely, I want to keep the observations unchaged if the observation concerns the age_group of <1 years and 95 plus (age_group variable list is not numeric). For all the other cases, I am trying to multiply the observation values by 4. I initially used this command: gen new_var = old_var * 4 if age_group != "<1 year" but I cannot incorporate 95 plus age group in this command. Also, in a new variable list, observations for <1 age group are deleted, while I would just like to keep the previous value. Thanks!

[Joseph Coveney]

. . . I cannot incorporate 95 plus age group in this command. Also, in a new variable list, observations for <1 age group are deleted, while I would just like to keep the previous value.

Then first create the new variables as duplicates of the source variables so that they begin with the same values, and then multiply by four when the age group variable's values match either of the two criteria. Something like the following.

foreach var of varlist <your selected variables> {
    clonevar new_`var' = `var'
    replace new_`var' = new_`var' * 4 if inlist(age_group, "<1 year", "95 plus")
}

[Joseph Coveney]

As an addendum, you can do something like this, too

foreach var of varlist <your selected variables> {
    generate double new_`var' = cond(inlist(age_group, "<1 year", "95 plus"), `var' * 4, `var')
}

but I recommend the two-step approach in #2 above, instead. It's clearer and -clonevar- maintains variable attributes (especially, storage type) better.

[Joro Kolev]

And if what Joseph explained above is not solving your problem, provide a sample dataset using -dataex- and clarify with respect to this set what you want to do.

[Mari Verulashvili]

Then first create the new variables as duplicates of the source variables so that they begin with the same values, and then multiply by four when the age group variable's values match either of the two criteria. Something like the following.

foreach var of varlist <your selected variables> {
clonevar new_`var' = `var'
replace new_`var' = new_`var' * 4 if inlist(age_group, "<1 year", "95 plus")
}

Thanks! I think this is doing the opposite of what I am trying, however. When running the code, it multiplies the values by 4 for when age group is <1 year and 95 plus. I am trying to maintain values for these age groups only and change ther rest (1 to 4, 5 to 9...e tc)

[Joseph Coveney]

I think this is doing the opposite of what I am trying, however. When running the code, it multiplies the values by 4 for when age group is <1 year and 95 plus. I am trying to maintain values for these age groups only and change ther rest (1 to 4, 5 to 9...e tc)

Whoops, sorry. Flip the Boolean condition like this.

replace new_`var' = new_`var' * 4 if !inlist(age_group, "<1 year", "95 plus")

[Mari Verulashvili]

Whoops, sorry. Flip the Boolean condition like this.

replace new_`var' = new_`var' * 4 if !inlist(age_group, "<1 year", "95 plus")

Thanks so much!