lecture 7

Question 1

poka yoke

Answer 1

• every company should reduce and prevent mistakes from happening –> a poka-yoke helps an equipment operator to avoid mistakes (mistake-proof/fail-safe)
• definition : prevent mistakes from happening by correcting, preventing, and drawing attention to human errors as they occur –> after the fact does not count

Question 2

3 types of T errors

Answer 2

1. task error : work was done incorrectly, wrong order, was not requested, or too slow (process error, does not include insufficient service capacity)
2. treatment error : failure to acknowledge, listen, or react to the customer appropriately (not polite to customers)
3. tangible error : mistakes that the customer can detect via 5 senses)

Question 3

ritz-carlton’s customer service

Answer 3

they meet customers’ expressed and unexpressed needs

Question 4

How ritz calrton get their superior customer service

Answer 4

• hire and train employees for service excellence
• respect their employees
• employee empowerment –> good pay
• teamwork (line up, first class cards –> give to employees, recognize their outstanding actions)

Question 5

m/m/c queueing model

Answer 5

• mathematical study of queuing lines/waiting lines
• 1st M = memoryless interarrival time, 2nd M = memoryless service time, c = number of servers
• queuing model = customer arrives –> busy : wait in queue –> servers start to serve –> service is completed

Question 6

m/m/c model output

Answer 6

• average queue length (L)
• average wait time (W)
• average total time = average wait time + average service time

Question 7

how to decrease L and W

Answer 7

1. more servers
2. increase service rate/decrease service time
3. decreasing variability in service time and interarrival

Question 8

increase in variability equals to

Answer 8

increase in wait time

Question 9

the service capacity in queue length is

Answer 9

non linear –> small change in service capacity = big change in wait time

Question 10

psychology of waiting

Answer 10

• an occupied wait feels shorter than an unoccupied wait
• an in-process wait feels shorter than a pre-process wait
• a known, finite wait feels shorter than an uncertain wait
• an explained wait feels shorter than an unexpected wait
• the more valuable the service is, the longer people would wait
• an equitable wait feels shorter than an unfair wait
• group waits feel shorter than solo waits
• a long wait would feel shorter if it was broken down to smaller shorter waits