EVE Technology Lab

Does anyone know the formula(s) needed for calculating the standings penalty incurred for turning down missions within the usual 4 hour recycle window?

I'd like to develop a script or spreadsheet that can tell me when I can turn down a mission safely for any of my characters.

I realise there are various situations such as (for example) when you can turn down a mission if your alliance standings are high enough and your agent won't fall below -2.00 as a result of the pentalty. What I'd like to get to the bottom of though, is what the mathematical formula is that can accurately predict the standing penalty incurred by turning down a mission within the first 4 hours of it being offered. The point of the script would be to let me know if I can do this without losing the agent.

From what I've seen, my characters seem to get different standing penalties in these situations, so perhaps this is skills related too. That's why I'd like to develop something that can take away the guesswork, thereby (hopefully) gaining me time by getting more of the mission types I like, and not losing any time by accidentally losing agents and having to put work back into getting them back online.