Peta Kontrol (Untuk Data Variabel)
Peta Kontrol (Untuk Data Variabel)
Variabel dan Atribute
• Pengertian Variabel
• Pengertian Atribut
• Perbedaan antara variabel dan atribut
Data Group
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Tujuan analisa kemampuan proses
Sumber-sumber keuangan
Urut-urutan produksi
Identifikasi bagan kendali yang berasal dari
sumber-sumber subgroup yang berbeda
• Indeks kemampuan proses
• Eksperimentasi
np-chart
• The np Chart can be used for the special case
when the subgroups are of equal size. Then it is
not necessary to convert nonconforming counts
into the proportions phat(i). Rather, one can
directly plot the counts x(i) versus the subgroup
number i.
Tahap-tahap Membuat np Chart
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Determine the size of the subgroups needed. The size,
n, has to be sufficiently large to have defects present in
the subgroup most of the time. If we have some idea
as to what the historical rate of nonconformance, p, is
we can use the following formula to estimate the
subgroup size:
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n=3/p
Find find pbar.
• Find the UCL and LCL where:
• Plot the centerline pbar, the LCL and UCL, and the
process nonconforming counts, the x(i)'s.
• Interpret the control chart. Only if a point is outside the
+/- 3 sigma range is the process considered to be out of
control.