Download Chapter 10 Sampling Terminology Parameter vs. Statistic

Basic Practice of Statistics - 3rd Edition
Case Study
Making Computer Monitors
Need to control the tension in millivolts
(mV) on the mesh of fine wires behind the
surface of the screen.
– Proper tension is 275 mV (target mean µ)
– When in control, the standard deviation of
the tension readings is σ=43 mV
Chapter 10
BPS - 3rd Ed.
25
Case Study
Making Computer Monitors
Proper tension is 275 mV (target mean µ). When in control, the
standard deviation of the tension readings is σ=43 mV.
Take samples of n=4 screens and calculate the
means of these samples
– the control limits of the x-bar control chart would be
µ±3
σ
n
= 275 ± 3
( ) = 275 ± 64.5
43
4
= 210.5 and 339.5
BPS - 3rd Ed.
Chapter 10
26
Case Study
Making
Computer
Monitors
(data)
BPS - 3rd Ed.
Chapter 10
Chapter 10
27
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