X-Man Problems

1
X-Man Problems

• Dr. Everette S. Gardner, Jr.

2
Terry Collins, CEO, Wildflour Pizza

• Terry Collins, CEO of Wildflour Pizza in
  Missouri City, Texas, collects data concerning
  customer complaints about delivery. Here are the
  results for the last 30 days
• Problem Frequency
• Topping stuck to box lid 17
• Pizza is late 35
• Wrong topping/combination 9
• Wrong style of crust 6
• Wrong size 4
• Pizza is partially eaten 3
• Pizza never showed up 6
• Total 80
• Assignment
• 1. Use a Pareto chart to help Terry identify
  the vital delivery problems.
• 2. Draw a fishbone chart to help Terry identify
  potential causes of late pizza delivery.

3
Country Star Nissan, Rosenberg, Texas

• David Lee Murphy, General Manager of the Country
  Star Nissan dealership in Rosenberg, Texas, liked
  to get to the office early so that he could
  practice guitar riffs before the business day
  started. He had just cranked up Dust on the
  Bottle when his secretary, Patty Loveless,
  barged in. Patty looked flustered and said,
  David Lee, you better put down that fool guitar
  and look at this letter. The contents are
  reproduced below
• Dear Mr. Murphy
• I am writing this letter to make you aware of a
  nightmare I experienced in getting my 300ZX
  repaired in your body shop and service
  department. Here is a chronology of events
• August 28
• Dropped off the car for repair of rust damage on
  roof along windshield area, left rocker panel
  under drivers door, and left quarter panel near
  end of bumper.
• September 1
• Called to inquire about the status of the car
  (this was the fifth day in the shop). Was told I
  could pick up the car anytime after 2 pm. My
  boyfriend and I arrived at 5 pm but the car was
  not ready. I paid the bill of 443.17 and
  waited. At 6 pm, the car was driven up dripping
  wet. (I assume the car was washed but cant you
  dry it off before you return it?) I got in and
  noticed the courtesy light in the drivers door
  would not go off when the door was closed. I
  asked for help and Pam Tillis, body shop manager,
  could not figure out what was wrong. She removed
  the bulb and told me to come back after Labor
  Day. I started the engine and drove off but the
  voice warning Left door is open repeatedly
  sounded. There was no way to turn it off. I
  returned to Ms. Tillis and told her to keep the
  car until it was fixed. Ms. Tillis told me to
  call the next day (Saturday).
• September 2
• I called Ms. Tillis at 1030 am. She said that
  the car had not been looked at yet. She promised
  to call back before the shop closed for the
  holiday but she never did.
• September 5
• I called Ms. Tillis at 4 pm. Nothing had been
  done but the car would be ready the next day.

4
Country Star Nissan, Rosenberg, Texas

• September 6
• I called Ms. Tillis at 3 pm. She said that the
  service department needed authorization to fix
  the car and they didnt know how much it would
  cost. I became very upset at the hint that I
  would have to pay to fix the door light and voice
  warning. I demanded to see the service manager,
  Shania Twain. She assured me that I was not
  financially responsible for any problems caused
  by the body shop. Furthermore, my car would be
  ready the next day.
• September 7
• Again late in the day, I called Ms. Twain. She
  said her best mechanic, Lorrie Morgan, had
  narrowed down the problem to a wire that passed
  several spots where body work was done. She
  referred the call to Ms. Morgan, who assured me
  that the car would be ready tomorrow.
• September 8
• I called Ms. Twain to check on the status. She
  told me that the wiring was fixed but the
  speedometer didnt work. Lorrie Morgan got on
  the line and said that when she test-drove the
  car, the speedometer pinned itself at the top
  end. She thought that one of the other mechanics
  must have done something to the speedometer while
  searching for the other problem. She told me
  that I could pick up the car but I would have to
  return in next Monday so that a subcontractor
  could fix the speedometer. Ms. Twain said that
  Ft. Bend Nissan would pay all charges.
• I arrived at 5 pm. As I walked up to the car, I
  noticed rubber molding hanging down below the
  drivers door. I asked Ms. Twain to come and
  look at it. She said that it must have come
  loose while they were repairing the wiring
  problem. She took the car back into the shop to
  screw the molding back in. When she finished,
  the molding looked sloppy. I complained about
  this and Ms. Twain said they would replace the
  molding next Monday. Driving home, I discovered
  that the anti-theft light on the dash would not
  stop blinking. I had to remove the fuse to stop
  the blinking light but this de-activated the
  security system.
• September 11
• On Sunday evening, I dropped the car off and
  left a note with my keys in the early-bird
  slot. The note listed the following problems
  molding, speedometer, and security system. I
  explained that all of these things were o.k. when
  I originally brought the car in for body work.
  On Monday, I got a call from Tanya Tucker in the
  service department who said that it would cost
  110 to repair the security system. The problems
  were in the hatchback lock and in the wiring of
  the system. I asked her why I had to pay for
  problems caused by Country Star Nissan.

5
Country Star Nissan, Rosenberg, Texas

• Ms. Tucker said that she had checked with the
  mechanics who worked on my carthere was no way
  they caused the problems with the security
  system. I told Ms. Tucker to forget the security
  system for now because I would take the problem
  up with the general manager. I asked Ms. Tucker
  to get the molding and speedometer fixed and get
  the car ready as soon as possible.
• September 13
• Ms. Tucker called and said I could pick the car
  up at 8 pm. I arrived at that time and was
  presented a bill for 126 for speedometer repair
  and miscellaneous labor in searching for the
  security system problem. I refused to pay the
  bill. I was told to take the car homethe
  service manager would resolve the problem the
  next day. I asked about the molding and was
  informed that it was not in stock and must be
  ordered. Note that the molding was damaged on
  September 8.
• As I got into the car, I noticed that the
  rear-view mirror was broken off its mounting and
  was lying in the passenger seat. I asked to see
  Ms. Twain and demanded to know how something like
  this could happen without anyone noticing. Ms.
  Twain was not in but I talked to Mary
  Chapin-Carpenter, who said someone probably did
  not want to own up to it. Ms. Chapin-Carpenter
  went to the parts department and got a new mirror
  and installed it.
• I realize this is a long letter, but I am
  extremely frustrated and upset by the mistakes
  made by your dealership over the last three
  weeks. What are you going to do about it?
• Sincerely,
• Leann Rimes
• Assignment
• 1. Categorize the quality problems in this
  case.
• 2. Prepare a fishbone chart for failure to
  resolve repair problem to customers
• satisfaction.

6
The X-Man and Mammy Faye Baker

• The X-Man is an ace relief pitcher and forkball
  specialist. During off-season periods, X has
  developed a considerable international reputation
  as an expert in quality assurance, management,
  and control. Currently he serves as a senior
  quality analyst at Mammy Lash, Inc., a company
  located in Palestine, Texas, and founded by Mammy
  Faye Baker. Mammy Lash manufactures eye shadow,
  false eyelashes, and a variety of other
  eye-related beauty products.
• Mammy Faye is concerned about the length of the
  horse hairs used in making eyelashes. Horse
  hairs were selected as a raw material because
  they are quite durable, although precision
  trimming is difficult. Therefore, X decided to
  sample the trimming process. He took 4 samples
  of size 3 each with the following results
• Sample Measurements
• 1 21 23 22
• 2 20 23 17
• 3 21 21 21
• 4 21 20 19
• To simplify calculations, the measurements are
  stated as the number of millimeters above 150.
  That is, the first measurement is actually 171
  millimeters (6.73 inches), the second is 173
  millimeters (6.81 inches), and so on.
• Help the X-Man answer the following questions
• 1. Is the trimming process in control?
• 2. Mammy Faye decides that specifications for
  eyelash hair length be established.
• The upper specification limit is 175
  millimeters, with a lower specification limit of
• 165. Is the trimming process capable?

7
The X-Man and the Vampire

• The alert student will recall that the X-Man
  took an off-season job as quality analyst at
  Mammy Lash, Inc., a manufacturer of eye-related
  beauty products. X is faced with another serious
  quality problem, this time involving Mammy Lashs
  Vampire Bat eye shadow, which most consumers
  purchase in the personal size (by the barrel).
  Each barrel should contain approximately 55
  pounds of eye shadow. Mammy Faye Baker is
  concerned about variation in actual weights of
  barrel contents.
• X weighed 5 samples, each containing 4 barrels.
  He found that the mean of the sample means was
  54.4 pounds, while the mean of the sample ranges
  was 3.2 pounds.
• Help the X-Man answer Mammy Fayes questions
• 1. What are the 3-standard-deviation control
  limits for the sample means and
• ranges?
• 2. What percentage of sample means should fall
  inside the 3-standard-deviation
• control limits, if the process is actually
  in control? What percentage should fall
• outside the limits?
• 3. What is the range of expected natural or
  common-cause variation for individual
• observations?
• 4. What percentage of individual observations
  should fall inside the range of natural
• or common-cause variation? What percentage
  should fall outside the limits?
• 5. Mammy Faye would like to have
  2-standard-deviation limits for means and ranges

8
The X-Man and Roberto Alomar

• The X-Man became increasingly unhappy in his
  off-season job at Mammy Lash, Inc. The last
  straw was a memo from Mammy Faye Baker stating
  that all employees must report to work each day
  wearing a complete collection of Mammy Lash
  products.
• X moved back to Missouri City, Texas, where he
  took a job as Senior Vice President for Quality
  Assurance and Control at Wildflour Pizza. The
  alert student will recall that Wildflour
  customers sometimes complain that pizzas are
  delivered in a partially-eaten condition.
  Wildflours CEO, Terry Collins, asked X to
  analyze this problem.
• X collected data for deliveries during the first
  5 days of November
• complaints that
• Sample Driver
  delivered pizza is partially eaten
• 1 Roberto Alomar
  1,000 4
• 2 Orlando Miller 300
  1
• 3 Roberto Alomar 1,500
  14
• 4 Orlando Miller 1,000
  0
• 5 Roberto Alomar 100
  3
• Help the X-Man answer the following questions
• 1. What type of control chart should be used to
  monitor these complaints?
• 2. Compute upper and lower control limits for
  the chart that you selected in question 1.
• 3. Is the process in control? Why or why not?
• 4. What assumptions about the data are
  necessary to use your chart?

9
The X-Man and the Alligator

• The alert student will recall that the X-Man
  took a position as Senior Vice President for
  Quality Assurance and Control at Wildflour Pizza,
  Missouri City, Texas. Xs first project at
  Wildflour was an investigation of customer
  complaints about partially-eaten pizzas. X
  solved that problem by suspending the culprit,
  Roberto Alomar, for five days. Although
  Robertos union, the Pizza Teamsters, requested
  that the suspension be served during the
  off-season next year, X did not give in and
  Roberto served his sentence.
• Another quality problem has cropped up at
  Wildflour. The CEO, Larry Dierker (who replaced
  Terry Collins at both Wildflour and the Astros),
  built a Cajun Sushi Bar at Wildflours main
  restaurant location on Murphy Road, near Highway
  6. The Bar proved to be wildly popular,
  primarily due to its Alligator Sushi, composed of
  paper-thin slices of fresh alligator marinated in
  corn liquor.
• To ensure freshness of the product, Wildflour
  receives one live alligator each day from its
  supplier in Hope, Arkansas. Alligator processing
  is a spectator sport at Wildflour. When each
  alligator arrives, it is thrown into a pit in the
  center of the restaurant. Accompanied by
  applause and cheers from customers, the executive
  chef, Danny Darwin, dives into the pit and
  wrestles the alligator into submission. At this
  point, Danny takes a much-needed shower while his
  assistant, John Cangelosi, takes over. John
  slays the beast, dresses it, and slices it. The
  last step in processing is a good dousing in corn
  liquor.
• Danny is concerned about the consistency of the
  dressed weights of alligators. He would like to
  receive alligators with dressed weights in a
  reasonable range of variation around 500 pounds,
  the Bars average daily demand. Weights much
  above 500 pounds result in wasted sushi, which
  cannot be retained overnight or it will lose its
  flavor. Weights much less than 500 pounds result
  in hungry customers that cannot be served.

10
The X-Man and the Alligator (cont.)

• Danny asked X to set up a control chart to
  monitor the daily dressed weights of alligators.
  Here are the weights collected by X for five
  consecutive days
• Day Dressed weight (lbs.)
• 1 495
• 2 517
• 3 488
• 4 505
• 5 541
• Help the X-Man answer the following questions
• 1. What type of control chart is appropriate
  for this data?
• 2. What are the upper and lower control limits?
• 3. Is the process in control? Why or why not?

11
The X-Man and Marvin Zindler

• Marvin Zindler paid a surprise visit to
  Wildflours Cajun Sushi Bar. Although Marvin
  liked the Gator Sushi, he was quite upset when he
  found slime in the ice machine. During his
  Channel 13 broadcast, Marvin became so agitated
  that his wig flew off.
• Wildflours owner, Drayton McClain, saw Marvins
  broadcast. He called the X-Man into his office,
  read him the riot act, and ordered him to design
  a quality inspection program for the companys
  nationwide chain of 5,675 restaurant units.
  Drayton also demanded a control chart to monitor
  inspection results.
• X decided to randomly select restaurant units
  for surprise inspections. Any quality problem in
  sanitation, restaurant design, equipment, food
  preparation, training, delivery, or customer
  service would be counted as a defect. Thus there
  were an extremely large number of opportunities
  for defects in any restaurant unit.
• Here are the results of Xs inspection program
  for the first 5 days
• Number of Number of
• Day restaurant units quality defects
• 1 1
  6
• 2 1
  3
• 3 1
  5
• 4 1
  2
• 5 1
  5
• Help the X-Man answer the following questions
• 1. What type of control chart is appropriate
  for this data?
• 2. Compute upper and lower control limits.

12
The X-Man and Marvin Zindler (cont.)

• Drayton was unhappy with the pace of Xs
  inspection program and told him to speed it up.
  Here are the results for the next 2 days
• Number of Number of
• Day restaurant units quality defects
• 6 2 10
• 7 4 23
• Add the new data to the previous sample and help
  the X-Man answer the following questions
• 1. What type of control chart is appropriate
  for the combined data set (days 1-7)?
• 2. Compute upper and lower control limits for
  the combined data set.
• 3. Is the process in control? Why or why not?

13
The X-Man and the Moonshine Saki

• The most popular cocktail served in Wildflours
  Cajun Sushi Bar is Moonshine Saki. According to
  Billy Wagner, the Houston Chronicles wine
  critic, Moonshine Saki is an audacious, uniquely
  Cajun interpretation of the original Japanese
  rice wine.
• Moonshine Saki is actually a blend, composed of
  fermented rice and pinto beans in a corn liquor
  base. The drink is served very warm, in a pint
  Mason jar, with a pinch of roux, a cayenne pepper
  floating on top, and sporting a green onion
  swizzle-stick. (Wagner recommends adding a shot
  of Tabasco to enhance the bouquet.)
• Drayton asked X to develop a control chart to
  monitor quarterly sales of Moonshine Saki. The
  table below shows sales in thousands of gallons
  for the last two years
• Year Qtr. Sales (000s)
• 1995 1 16
• 2 19
• 3 24
• 4 22
• 1996 1 17
• 2 21
• 3 23
• 4 21
• Help the X-Man perform the following tasks
• 1. Perform a seasonal adjustment of the data.
• 2. Use the seasonally-adjusted data to develop
  a control chart.