In a past life I tried to normalize this by adding the standard deviation of the rolling averages. And then triggered off of the new average. I also do not use rework in yield calculations at all. The yield info is first pass data.
Kat
>>> [log in to unmask] 12/27/02 12:09PM >>>
Does anyone have a standard way to normalize yield percentage charts for
wildly varying production volumes ?
My yield percentage charts show 50% yield when there is 1 out of 2
failures or 50 out of 100 failures.
The 50% Yield with 1 out of 2 usually happens during a Christmas week
when there is no production, only rework.
I have tried to normalize the charts by using a constant denominator
based on the nominal volume.
I use 13 week rolling averages but they are messed up by the low volume
yield results.
This low volume percentage reporting can cause incorrect corrective
actions.
Does anyone know of a standard way to normalize the data ?
Cronbach's Alpha,
Split-Half Reliability (Spearman-Brown Coefficient),
Attenuation correction,
Pair Wise Deletion of Missing Data,
Partial correlation,
Parzen Window,
Pearson Curves,
Johnson Curves ?
Paul Signorelli
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<DIV><FONT size=1>In a past life I tried to normalize this by adding the
standard deviation of the rolling averages. And then triggered off of the
new average. I also do not use rework in yield calculations at all.
The yield info is first pass data. </FONT></DIV>
<DIV><FONT size=1></FONT> </DIV>
<DIV><FONT size=1>Kat</FONT></DIV>
<DIV><BR><BR>>>> [log in to unmask] 12/27/02 12:09PM
>>><BR>Does anyone have a standard way to normalize yield percentage
charts for<BR>wildly varying production volumes ?<BR>My yield percentage charts
show 50% yield when there is 1 out of 2<BR>failures or 50 out of 100
failures.<BR>The 50% Yield with 1 out of 2 usually happens during a Christmas
week<BR>when there is no production, only rework.<BR>I have tried to normalize
the charts by using a constant denominator<BR>based on the nominal volume.<BR>I
use 13 week rolling averages but they are messed up by the low volume<BR>yield
results.<BR>This low volume percentage reporting can cause incorrect
corrective<BR>actions.<BR>Does anyone know of a standard way to normalize the
data ?<BR>Cronbach's Alpha,<BR>Split-Half Reliability (Spearman-Brown
Coefficient),<BR>Attenuation correction,<BR>Pair Wise Deletion of Missing
Data,<BR>Partial correlation,<BR>Parzen Window,<BR>Pearson Curves,<BR>Johnson
Curves ?<BR><BR>Paul
Signorelli<BR><BR>---------------------------------------------------<BR>Technet
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