The concept of rational sub group means that subgroups or samples be selected such that if assignable causes are present the chances for differences between subgroups will be ______________.

Related MCQs

• Control chart theory is based on the differences of the causes of variations in quality. Variations in quality may be produced by assignable causes. All of the following are examples of assignable causes except:
• An acceptance control chart has limits that are based on the specification limits for the product rather than limits which differentiate between random and assignable causes. Under which if the following circumstance should a QC manager consider using an acceptance control chart?
• Cause & Effect diagram used to i. Identify & organize possible causes of problem ii. Identify possible causes of solution iii. Identify possible causes of problem & determining its relation The correct order is
• An assignable variance tells us:
• Factory A produces 100 pieces of wooden legs used in manufacturing tables in 1 hour. The factory in total works for 3 hours. The quality manager decided to check the quality of the output by measuring the length of the legs (in cms). He decides to collect three samples (one for each hour). The sample size for each sample is fixed at 5. The data collected is present in the following table: What is the mean and range of leg length in sample 1?
• The thickness of the blade of a fan is specified to lie between 4 cm and 6 cm. The length of the blades must lie between 10 cm and 20 cm. A fan blade randomly selected from a sample of 100 blades has a thickness of 5cm and a length of 21cm. The number of defect(s) the blade has is ______________.
• You have carried out a Kruskal-Wallis test. There are significant differences between the three groups you are testing. How might you conduct your pair wise comparisons?
• If only ______________ causes of variation are present, the output of a process forms a distribution that is table over time and is predictable.
• Consider that for a process s bar (average standard deviation of 50 samples each of size 4) is found to be 10.04. The value of c4 (corresponding to sample size of .4) is .92. What is the estimated value of process standard deviation?
• Given that for the three samples, the value of R bar is .66 and value of d2 corresponding to three is1.128, what is the estimated standard deviation?