Exam 19: Statistical Applications in Quality Management

SCENARIO 19-8 Recently,a university switched to a new type of computer-based registration.The registrar is concerned with the amount of time students are spending on the computer registering under the new system.She decides to randomly select 8 students on each of the 12 days of the registration and determine the time each spends on the computer registering.The range,mean,and standard deviation of the times required to register are in the table that follows. -Referring to Scenario 19-8,an x̄ chart is to be used for the time required to register.The lower control limit for this data set is _____ ,while the upper control limit is _____ .

Larger C_pk indicates larger capability of meeting the requirements.

SCENARIO 19-7 A supplier of silicone sheets for producers of computer chips wants to evaluate her manufacturing process.She takes samples of size 5 from each day's output and counts the number of blemishes on each silicone sheet.The results from 20 days of such evaluations are presented below. She also decides that the upper specification limit is 10 blemishes. -Referring to Scenario 19-7,an x̄ chart is to be used for the number of blemishes.The center line of this chart is located at .

A master black belt is among the tools of Lean Six Sigma.

One of the morals of the red bead experiment is that variation is part of any process.

Quick Changeover Techniques establish ways to eliminate unnecessary housekeeping aspects of a work environment.

SCENARIO 19-7 A supplier of silicone sheets for producers of computer chips wants to evaluate her manufacturing process.She takes samples of size 5 from each day's output and counts the number of blemishes on each silicone sheet.The results from 20 days of such evaluations are presented below. She also decides that the upper specification limit is 10 blemishes. -Referring to Scenario 19-7,based on the x̄ chart for the number of blemishes,it appears that the process is out of control.

SCENARIO 19-3 A quality control analyst for a light bulb manufacturer is concerned that the time it takes to produce a batch of light bulbs is too erratic.Accordingly,the analyst randomly surveys 10 production periods each day for 14 days and records the sample mean and range for each day. -Referring to Scenario 19-3,suppose the analyst constructs an x̄ chart to see if the production process is in-control.What is the upper control limit (UCL)for this chart?

Which of the following best measures the ability of a process to consistently meet specified customer-driven requirements?

SS method is among the tools of Lean Six Sigma.

Special or assignable causes of variation are signaled by individual fluctuations or patterns in the data.

One of the morals of the red bead experiment is:

SCENARIO 19-9 The manufacturer of canned food constructed control charts and analyzed several quality characteristics.One characteristic of interest is the weight of the filled cans.The lower specification limit for weight is 2.95 pounds.The table below provides the range and mean of the weights of five cans tested every fifteen minutes during a day's production. -Referring to Scenario 19-9,an R chart is to be constructed for the weight.One way to create the lower control limit involves multiplying the mean of the sample ranges by D₃.For this data set,the value of D₃ is .

SCENARIO 19-2 A political pollster randomly selects a sample of 100 voters each day for 8 successive days and asks how many will vote for the incumbent.The pollster wishes to construct a p chart to see if the percentage favoring the incumbent candidate is too erratic. -Referring to Scenario 19-2,what is the numerical value of the upper control limit for the p chart?

SCENARIO 19-9 The manufacturer of canned food constructed control charts and analyzed several quality characteristics.One characteristic of interest is the weight of the filled cans.The lower specification limit for weight is 2.95 pounds.The table below provides the range and mean of the weights of five cans tested every fifteen minutes during a day's production. -Referring to Scenario 19-9,estimate the percentage of the cans whose weight is inside the specification limit.

SCENARIO 19-8 Recently,a university switched to a new type of computer-based registration.The registrar is concerned with the amount of time students are spending on the computer registering under the new system.She decides to randomly select 8 students on each of the 12 days of the registration and determine the time each spends on the computer registering.The range,mean,and standard deviation of the times required to register are in the table that follows. -Referring to Scenario 19-8,based on the x̄ chart,it appears that the process is in control.

The p chart is a control chart used for monitoring the proportion of items that meet given specifications.

Mistake Proofing (Poke-Yoke)devices focus on preventing the causes of defects.

SCENARIO 19-6 The maker of a packaged candy wants to evaluate the quality of her production process.On each of 16 consecutive days,she samples 600 bags of candy and determines the number in each day's sample that she considers to be of poor quality.The data that she developed follow. -Referring to Scenario 19-6,the estimate of the proportion of poor quality bags of candy is .

SCENARIO 19-2 A political pollster randomly selects a sample of 100 voters each day for 8 successive days and asks how many will vote for the incumbent.The pollster wishes to construct a p chart to see if the percentage favoring the incumbent candidate is too erratic. -Referring to Scenario 19-2,what is the numerical value of the center line for the p chart?