Operations mgmt with std dvd 9e – problems set

The manager of a travel agency has been using a seasonally adjusted forecast to predict demand for packaged tours. The actual and predicted values are…

The manager of a travel agency has been using a seasonally adjusted forecast to predict demand for packaged tours. The actual and predicted values are as follows:
     
Period  DemandPredicted
1138        111        
2194        200        
3157        150        
491        94        
595        80        
6132        144        
7126        128        
8127        124        
995        96        
10149        150        
11104        94        
1285        75        
13120        140        
14134        128        
________________________________________
     
a.Compute MAD for the fifth period, then update it period by period using exponential smoothing with α = .1.(Round your intermediate calculations and final answers to 3 decimal places.)
      
t
PeriodA
Demand    MADt
1138        
2194        
3157        
491        
595         

6132         

7126         

8127         

995         

10149         

11104         

1285         

13120         

14134         

________________________________________
      
b.Compute a tracking signal for periods 5 through 14 using the initial and updated MADs. (Negative values should be indicated by a minus sign. Round your intermediate calculations and final answers to 3 decimal places.)
      
t
PeriodA
DemandTracking
Signal
1138        
2194        
3157        
491        
595         

6132         

7126         

8127         

995         

10149         

11104         

1285         

13120         

14134         

________________________________________

Checkout time at a supermarket is monitored using a mean and a range chart. Six samples of n = 20 observations have been obtained and the sample means and ranges computed:

SampleMeanRangeSampleMeanRange
13.06.4243.13.46
23.15.4453.06.46
33.11.4163.09.45
________________________________________
Q 2,
Factors for three-sigma control limits for  and R charts

FACTORS FOR R CHARTS
Number of Observations in Subgroup,
nFactor for
 Chart,
A2Lower
Control Limit,
D3Upper
Control Limit,
D4
2           1.88         03.27
3           1.02         02.57
4           0.73         02.28
5           0.58         02.11
6           0.48         02.00
7           0.42         0.081.92
8           0.37         0.141.86
9           0.34         0.181.82
10           0.31         0.221.78
11           0.29         0.261.74
12           0.27         0.281.72
13           0.25         0.311.69
14           0.24         0.331.67
15           0.22         0.351.65
16           0.21         0.361.64
17           0.20         0.381.62
18           0.19         0.391.61
19           0.19         0.401.60
20           0.18         0.411.59
________________________________________

a.Using the factors in the above table, determine upper and lower limits for mean and range charts.(Round your intermediate calculations and final answers to 4 decimal places.)

  Upper limit for mean   
  Lower limit for mean   
  Upper limit for range   
  Lower limit for range   
_______________________________________
b.Is the process in control?
  
Yes
 No
Let’s block ads! (Why?)

Do you need any assistance with this question?
Send us your paper details now
We’ll find the best professional writer for you!

 



error: Content is protected !!