Questions

docx

School

Baruch College, CUNY *

*We aren’t endorsed by this school

Course

OPM 3000

Subject

Industrial Engineering

Date

Dec 6, 2023

Type

docx

Pages

Uploaded by AgentBraveryRook41

1."Assignable/special' variation is due to special causes that can and should usually be anticipated, and controlled by management" No Yes 2. Which of the following is most likely a special cause of variation in the process/unit? A regularly malfunctioning fryer in a PopEyes fast food place An occasionally malfunctioning fryer in a PopEyes fast food place -3. Which of the following variations is most likely to be driven by a common cause? An increase in Holland tunnel traffic jams because of a SuperBowl in NYC A snowfall delaying a flight in winter A student improving her grade from an C to an A, because she studied early and hard, for an exam A surge of guests at an airport hotel because of a sudden mechanical breakdown of a plane 4. We are drawing many samples at regular intervals from our bottling process that has been previously brought 'in statistical control'. The most current sample point happens to falls outside the upper control limit (+- 3 sigma). Should we: Stop sampling, stop the process, and search for a special cause? Continue with the sampling of the running process and wait to see if another sample point falls out of control? Just one out of control point in a regular sampling process signifies very little - there is a high probability of an individual sample point falling out of the +- 3 sigma control limits just by chance. seeing that we are sampling regularly. Just suspend sampling for a while and give the process a chance to re-set itself? Continue with the sampling - it's just a random common cause driven event that we cannot anticipate or control well. 5. After getting a process into statistical control, a range chart was developed (3-sigma limits) with LCL=0 and UCL=2.50. Similarly an average chart was developed (3 sigma limits) with LCL=15 and UCL=24. Five monitoring samples subsequently taken read as follows: sample ranges: 1.75, 2.42, 1.82, 2.04, 2.80, and sample means: 19.5, 22.3, 17.4, 20.1, 22, respectively. What can you tell management from this analysis? (Hint: See 'quality control charts - audio' in quality folder on BB/course documents/).

The process is not in statistical control, since both process variability and the process average need to be within their respective control limits, in order for it to be so. We cannot tell anything from the data provided. T he process variability is out of control, but it is a good thing, practically speaking. The process is still in statistical control since the process average is in control, although the process variability is out of control. 6. "The proportion of students earning an ""A"" in a course is a ___________ characteristic" Variable "Attribute (Got an A or Did not get an A)" 7. A process in ""statistical control"" would still show some variation, but that variation would primarily be driven by "common" random/natural causes ? False True 8. Fixing a UCL and LCL at 3 standard deviations (take area as 99.73%) means that the probability of making a Type 1 error is approximately: "0.135% for each tail (above or below the UCL and LCL, respectively)" "2.5% for each tail (above or below the UCL and LCL, respectively)" "0.30% for each tail (above or below the UCL and LCL, respectively)" "99.7% for each tail (above or below the UCL and LCL, respectively)" 9. "X and R charts are used to track ___________ and ___________ respectively, of ___________ type of variables" Proportion and ranges of attribute "Averages and ranges, of continuous (variable)"

10. "In a R chart monitoring the average range of response times to a 911 call, a sample's range falls above the UCL. Is that good or bad news?" "Bad news, both statistically and practically speaking" "Good news, both statistically and practically speaking" "Bad news, statistically speaking, but good news, practically speaking" of the following variations is most likely to be driven by a common cause -11. In examining the performance of a process, what would constitute an 'out of statistical control' situation using +- 3 sigma control limits? Please pick the most appropriate response from the options provided. (Hint: See file 'How to read a control chart' audio on BB/quality folder/) A sample falls outside the control limits of both the Xbar and R charts All of the above situations signify an out of statistical control process A sample falls outside the control limits of the Xbar chart, but stays within the control limits of the R chart A sample falls outside the control limits of the R chart, but stays within the control limits of the X bar chart 12. Workers, rather than managers, are responsible for cleaning a process of "special" causes, thus bringing it under "statistical control". Yes No 13. "Quality characteristics can generally be measured in ""variable"" (continuous) and/or attribute (yes/no) format". (Hint: See file 'quality control charts audio') Yes No 14. Speed (mph) is a ________ characteristic (HInt: See quality control charts - audio) Variable (can be measured in continuous decimal form) Attribute

Your preview ends here

Eager to read complete document? Join bartleby learn and gain access to the full version

Access to all documents
Unlimited textbook solutions
24/7 expert homework help

15. "Common/Random/natural' variation is driven by random causes that occur naturally and are difficult to predict or control" Yes No 16. SQC (statistical quality control) uses charts to monitor special causes that may return again to a system that has been brought under "statistical control". Yes No 17. Contracting (narrowing) the UCL and LCL would increase or decrease the probability of making a type 1 error? Increase Decrease Neither increase or decrease the probability of making a type 1 error 18. "A type 1 error occurs when we conclude that the mean of the process has changed (based on a sample mean falling outside the control limits), when in fact it has not. " True False 19. P charts are used to track ___________ of ___________ type of variables Proportion defective of attribute type measurement data Averages of continuous type measurement data 20. A process that is in ""statistical control"" is one where all assignable (special) causes have been identified and addressed? True False

Questions

Related Documents