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

---------------------------------------------------
Technet Mail List provided as a free service by IPC using LISTSERV 1.8e
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest
Search the archives of previous posts at: http://listserv.ipc.org/archives
Please visit IPC web site http://www.ipc.org/html/forum.htm for additional
information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315
-----------------------------------------------------