David Christopher received his medical degrees from the University of Kentucky and the

University of Virginia. He did his residency and early surgeries at Duke University Medical

Center. Eight years ago he set up his own orthopedic surgery clinic in Atlanta, Georgia. Today,

one other doctor has joined his clinic in addition to $12$ support personnel such as X$-$ray

technicians, nurses, accounting, and office support. The medical practice specializes in all

orthopedic surgery, except it does not perform spinal surgery. The clinic has grown to the point

where both orthopedic surgeons are working long hours, and Dr$.$ Christopher is wondering

whether he needs to hire more surgeons.

An orthopedic surgeon is trained in the preservation, investigation, and restoration of the form

and function of the extremities, spine, and associated structures by medical, surgical, and

physical means. He or she is involved with the care of patients whose musculoskeletal problems

include congenital deformities; trauma; infections; tumors; metabolic disturbances of the

musculoskeletal system; deformities; injuries; and degenerative diseases of the spine, hands, feet,

knee, hip, shoulder, and elbows in children and adults. An orthopedic surgeon is also concerned

with primary and secondary muscular problems and the effects of central or peripheral nervous

system lesions of the musculoskeletal system. Osteoporosis, for example, results in fractures,

especially in the hips, wrists, and spine. Treatments have been very successful in getting the

fractures to heal.

Dr$.$ Christopher collected the data of the clinic$$s typical workweek. Both surgeons work $11$ hours

each day, with $1$ hour off for lunch, or $10$ effective hours. All surgeries are performed from $7$:$00$

a$.$m$.$ to $12$:$00$ noon, $4$ days a week. After lunch, the surgeons see patients in the hospital and at

the clinic from $1$:$00$ p$.$m$.$ to $6$:$00$ p$.$m$.$ Over the weekend and on Fridays, the surgeons rest, attend

conferences and professional meetings, and sometimes do guest lectures at a nearby medical

school. The doctors want to leave a safety capacity each week of $10$ percent for unexpected

problems with scheduled surgeries and emergency patient arrivals.

The setup and changeover times in Table $1$ reflect time allowed between each surgery for the

surgeons to clean themselves up$,$ rest, review the next patient$$s medical record for any last$-$

minute issues, and prepare for the next surgery. Dr$.$ Christopher feels these changeover times

help ensure the quality of their surgery by giving them time between operations. For example,

standing on a concrete floor and bending over a patient in a state of concentration places great

stress on the surgeon$$s legs and back. Dr$.$ Christopher likes to sit down for a while between

surgeries to relax. Some surgeons go quickly from one patient to the next; however, Dr$.$

Christopher thinks this practice of rushing could lead to medical and surgical errors.

$($See Table $1$ and Table $2)$

$1.$Dr$.$ Christopher keeps a record of the service time in the past $16$ weeks $($Table $2)$ and

wants to plan in advance for future service. What will be the forecast for the service time for

week $17$ if Dr$.$ Christopher only considers time as a factor? Using three weeks simple moving

average and single exponential smoothing $(\backslash$alpha $=0\mathrm{.}2)(10$pt$).$ Comparing simple moving

averages with single exponential smoothing, which method provides Dr$.$ Christopher a better

idea of service time. Please provide an analysis to verify your answers $(10$pt$).$

$2.$ Meanwhile, Dr$.$ Christopher thinks that the average costs for service may be an important

factor affecting service demand. To have a better understanding of the future service time

demand, Dr$.$ Christopher decided to include average costs in the service time forecasting.

Please utilize the information in Table $2$ to predict the service time for week $17$ if the average

costs for week $17$ are predicted at $$140.$ Which factor time or average costs has more impact

on service demand? Please provide verification of your answers $(10$pt$)$

$3.$ Dr$.$ Christopher has two options to increase service time in the near future: one is to hire a

surgeon with a $$3,000$ weekly payment. The variable cost of serving a patient is $$100$ with an

average service time of $100$ minutes. The other is to contract another surgery clinic with a

variable cost of servicing a patient of $$700.$ Based on the predicted service time from

question $5,$ which options Dr$.$ Christopher should go with? Why?