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Signed/directed deviation?

Signed/directed deviation?

Signed/directed deviation?


I am measuring the relative deviations of some variables according to a formula given as follows:

Dev. % = 100 * (Value_Predicted - Value_Measured) / Value_Predicted

For some variables, when Dev. > 0 it means performance of the process is improving (i.e. the higher the Dev., the higher the performance).
For some other variables, it works the opposite way (i.e. the lower the Dev., the higher the performance).

I am displaying the Dev. of all variables in a X-Y chart.
On the X-axis there is <time T(s)> and on the Y-axis the deviations <Dev. (%)>.

I want to make it so that on the Y-axis, instead of displaying <Dev.> I would use a new indicator in such a way that an increase always corresponds to performance improvement and vice versa. Thus I corrected the original deviations as follows:

Dev_New = sign_function() * Dev_Original

sign_function() would take (1) or (-1) to reverse when it is needed.

My question, how do you call this new indicator: Dev_New?

- Directed deviation
- Signed deviation
- ...?

Any suggestions would be appreciated.


If you plan an escape, you must succeed as if you fail, you will be punished for trying. Never say or write down your plan. Heart is the only place where secrecy is granted.

RE: Signed/directed deviation?

Percent improvement.

RE: Signed/directed deviation?

...and the negative of Improvement might be...


...for those Y values below the X axis.


glassesJust traded in my OLD subtlety...
for a NUance!tongue

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