date of a a variable from two other variables

[dr_101]

thanks.

[PeterClemmensen]

Can you provide some sample data and what you want the result to look like? Makes it much easier to provide a usable syntax solution.

[Reeza]

This can be done in two steps assuming you have full data, which is what I suspect they're looking for here. It sounds like an interview question so I would suggest searching on how to calculate prevalence. The answer to this question is on the forum. Besides that, this sounds like an interview question that's meant to reflect your skill level and knowledge so you should try to do this on your own.

[Reeza]

Show an example of what you have and what you want as output.

[dr_101]

o

[Reeza]

Ok. You've posted two very different questions, COPD and birth rates/prevalence/incidence. 

When I ask for questions like this, I will be looking for three things:

1. Approach taken makes sense - check accuracy of numbers

2. Coding level

3. Comments and code organization

#2 and #3 matter as much if not more than #1. I can correct #1 very easily by telling someone the formula, changing peoples working styles is significantly harder. 

• (This should give no. of patients with atleats one birth) (a) -> why did you calculate this, instead of directly calculating the number of single births? 
• Why do you have so many data steps, can't they be combined?
• What is the purpose of each step?
• Why create the morbseq number when FIRST. already contains the same information?
• The final answer in your example is calculated manually, why not have the code do it directly?
• Not a single comment 😞

That's should be enough to help you improve your answers. Good Luck. 

[Patrick]

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@dr_101 wrote:

well i undestand what you are saying. but that's how its given in the excsercise that i need to follow. thanks

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May be read again what @Reeza posted as this is very valuable advise which you should try to follow.