LiquidSapphire
New member
- Joined
- Jan 31, 2013
- Messages
- 2
Percentiles of Percentiles -Question about combining results of multiple sets of data
Hello -
I am running a retirement simulation and wanted to run my statistics logic by someone smarter than me to see if this holds water.
I am using the calculator at firecalc.com - it is a retirement calculator. I am trying to find a certain annual spending level that will be successful 80% of the time (success = you don't run out of money) given a certain set of facts such as mean return, standard deviation of return, etc. The calculator can do this very well, the problem is that it will only run 181 trials at once, and every time I run it I get some significant variance.
I want to run many many more trials than 181, like say, 8000 trials. So what I did was I ran the calculator 45 times to get the number which, in the 181 trials it ran, was successful 80% of the time.
So now I have this set of 45 numbers that were successful 80% of the time in their respective trial. In other words, I ran 181 experiments 45 different times, and now I have a data set of 45 numbers where in each of those 45 times, I did not run out of money 80% of the time. I want to distill this down to 1 number instead of 45 numbers. I want to know what the 80% success rate is if one were to run 8000 trials. Do I take the average of them, or do I take the 80th percentile of them, or neither? Is there a way I can calculate the 80% success rate of 8000 trials by running 181 trials 45 times and looking at the 80% success rate of those mini trials?
If it makes a difference, I kept the parameters in the calculator the same every time, I only hit the "submit" button 45 times so I could see the result of the 181 trials 45 different times.
Hello -
I am running a retirement simulation and wanted to run my statistics logic by someone smarter than me to see if this holds water.
I am using the calculator at firecalc.com - it is a retirement calculator. I am trying to find a certain annual spending level that will be successful 80% of the time (success = you don't run out of money) given a certain set of facts such as mean return, standard deviation of return, etc. The calculator can do this very well, the problem is that it will only run 181 trials at once, and every time I run it I get some significant variance.
I want to run many many more trials than 181, like say, 8000 trials. So what I did was I ran the calculator 45 times to get the number which, in the 181 trials it ran, was successful 80% of the time.
So now I have this set of 45 numbers that were successful 80% of the time in their respective trial. In other words, I ran 181 experiments 45 different times, and now I have a data set of 45 numbers where in each of those 45 times, I did not run out of money 80% of the time. I want to distill this down to 1 number instead of 45 numbers. I want to know what the 80% success rate is if one were to run 8000 trials. Do I take the average of them, or do I take the 80th percentile of them, or neither? Is there a way I can calculate the 80% success rate of 8000 trials by running 181 trials 45 times and looking at the 80% success rate of those mini trials?
If it makes a difference, I kept the parameters in the calculator the same every time, I only hit the "submit" button 45 times so I could see the result of the 181 trials 45 different times.
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