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re: Re: st: simulated value of a ratio does not compare to manually calculated value
From
"Ariel Linden, DrPH" <[email protected]>
To
<[email protected]>
Subject
re: Re: st: simulated value of a ratio does not compare to manually calculated value
Date
Sat, 27 Apr 2013 10:12:35 -0400
Jeph and Austin,
You are absolutely correct! I didn't even consider that simple fact!
Thanks for bringing it to my attention.
Ariel
Date: Fri, 26 Apr 2013 16:44:32 -0400
From: Jeph Herrin <[email protected]>
Subject: Re: st: simulated value of a ratio does not compare to manually
calculated value
More specifically, if you run the original code and list the values, it is
clear that mse_ratio=mse_true/mse_tt:
+--------------------------------+
| mse_true mse_tt mse_ra~o |
|--------------------------------|
| .003547 .0322058 .1101363 |
| .0006413 .0662122 .0096851 |
| .0053084 .0249331 .2129068 |
| .0013864 .0317399 .0436803 |
| .000913 .0238286 .0383137 |
| .0022051 .0287689 .0766471 |
| .0147754 .0337151 .4382421 |
| .0133145 .0008774 15.17555 |
| .0006873 .0390971 .0175787 |
| .0054993 .0493028 .1115405 |
| .0007968 .0217611 .0366142 |
| .0030441 .0083029 .3666291 |
| .0020152 .064011 .0314826 |
| .0016439 .0557283 .0294992 |
| .0008482 .0004691 1.808224 |
| .00004 .0477381 .0008388 |
| .0030498 .0468981 .0650293 |
On 4/26/2013 4:36 PM, Austin Nichols wrote:
> Ariel Linden, DrPH <[email protected]>:
>
> The mean of a ratio generically does not equal the ratio of the means.
> Put
> sc mse_t*
> corr mse_t*
> g r=mse_tr/mse_tt
> su r mse_true mse_tt mse_ratio
>
> On Fri, Apr 26, 2013 at 4:28 PM, Ariel Linden, DrPH
> <[email protected]> wrote:
>> Hi All,
>>
>> Below is a simulation that I am running in which I generate a ratio
>> (mse_ratio) which is simply the ratio of the mse_true / mse_tt
>>
>> When running the simulation, the mse_ratio does not calculate correctly,
>> even though each component does come through correctly...
>>
>> More specifically, you can see from the output below that the mse_true =
>> .0038127, and the mse_tt = .0352618 , which should
>> elicit a ratio of .10812551
>>
>> However, the mse_ratio value is 91.79034.
>>
>> I cannot figure out what in my code is not working here... Any help is
>> appreciated... See my code below...
>>
>> Thanks in advance!
>>
>> Ariel
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