Question 1
A manager wishes to build a 3-sigma range chart for a process. The sample size is five, the mean of sample means is 16.01, and the average range is 5.3. From Table S6.1, the appropriate value of D
3 is 0, and D
4 is 2.115. The UCL and LCL for this range chart are
◦ 31.91 and 0.11.
◦ 11.2 and 0.
◦ 33.9 and 0.
◦ 6.3 and 0.
◦ 33.9 and 11.2.
Question 2
Plots of sample ranges indicate that the most recent value is below the lower control limit. What course of action would you recommend?
◦ The process is out of control; reject the last units produced.
◦ Since there is no obvious pattern in the measurements, variability is in control.
◦ One value outside the control limits is insufficient to warrant any action.
◦ Lower than expected dispersion is a desirable condition; there is no reason to investigate.
◦ Variation is not in control; investigate what created this condition.
Muscles of the lower extremity.
Population genetics sample question
Sample Problem from Raven’s Progressive Matrices
An ob/ob mouse and a control mouse.
Sample prescriptions of drugs for oral herpes infection.
Human beta-globin–complex locus control region