Forcasting- Seasonal Index Number 26, 27, 28,29, 30 page · PDF file ·...

13
[Type text] Assigment November 9 th Forcasting- Seasonal Index Number 26, 27, 28,29, 30 page 630-631 Statistical Techniques in Business and Economics Lind/Marchal/ Wathen

Transcript of Forcasting- Seasonal Index Number 26, 27, 28,29, 30 page · PDF file ·...

[Type text]

Assigment November 9th

Forcasting- Seasonal Index

Number 26, 27, 28,29, 30 page 630-631

Statistical Techniques in Business and Economics

Lind/Marchal/ Wathen

[Type text]

Number 26 page 630

The production of Reliable Manufacturing company for 2007 and part of 2008 follows

Month 2007

Production (thousands

2008 Production (thousands

Month 2007

Production (thousands

2008 Production (thousands

January 6 7 July 3 4 February 7 9 August 5 March 12 14 September 14 April 8 9 October 6 May 4 5 November 7 June 3 4 December 6

a. Using the ratio-to-moving average method, determine the specific seasonal for

July, Agustus, September 2007

Year Month Production

(thousands)

12

months

Total

12

months

Moving

Average

Centre

Moving

Average

Spesific

Seasonal

20

07

January 6

February 7

March 12

April 8

May 4

june 3

81 6.8

july 3 6.8 44.2

82 6.8

August 5 6.9 72.3

84 7.0

September 14 7.1 197.6

86 7.2

October 6

November 7

December 6

20

08

January 7

February 9

March 14

April 9

May 5

june 4

july 4

[Type text]

b. Assume that the specific seasonal in the following table are correct. Insert in the

table the specific seasonal you computed in part (a) for July, August, September

and determine the 12 typical seasonal indexes

2007 2008 2009 2010 2011 Average Adjusted

January 88.9 87.6 79.8 89.0 86.3 86.3

February 102.9 103.7 105.6 112.1 106.1 106.1

March 178.9 170.2 165.8 182.9 174.5 174.5

April 118.2 125.9 124.7 115.1 121.0 121.0

May 60.1 59.4 62.1 57.6 59.8 59.8

June 43.1 48.6 41.7 56.9 47.6 47.6

July 44.2 44 44.2 48.2 45.2 45.2

August 72.3 74 77.2 72.1 73.9 73.9

September 197.6 200.9 196.5 203.6 199.7 199.7

October 92.1 99 89.6 80.2 90.2 90.2

November 106.5 101.9 113.2 103.2 106.2 106.2

December 92.9 90.9 80.6 94.2 89.7 89.7

Total 1,200.0 1,200.0

c. Interpret the typical seasonal index

March, April, September are the high season period and July is the lowest season

Number 27 page 630

The sales of Andre’s Boutique for 2007 and part of 2008 are

Month 2007

Production (thousands

2008 Production (thousands

Month 2007

Production (thousands

2008 Production (thousands

January 78 65 July 81 65 February 72 60 August 85 61 March 80 72 September 90 75 April 110 97 October 98 May 92 86 November 115 June 86 72 December 130

[Type text]

a. Using the ratio-to-moving average method, determine the specific seasonal for

July, Agustus, September and October

Year Month Production

(thousands)

12

months

Total

12 months

Moving

Average

Centre Moving

Average

Spesific

Seasonal

20

07

January 78

February 72

March 80

April 110

May 92

june 86

1117 93.1

july 81 92.5 87.5

1104 92.0

August 85 91.5 92.9

1092 91.0

September 90 90.7 99.3

1084 90.3

October 98 89.8 109.1

1071 89.3

November 115

December 130

20

08

January 65

February 60

March 72

April 97

May 86

june 72

july 65

August 61

September 75

[Type text]

b. Assume that the specific seasonal in the following table are correct. Insert in the

table the specific seasonal you computed in part (a) for July, August, September

and October and determine the 12 typical seasonal indexes

2007 2008 2009 2010 2011 Average Adjusted

January 83.9 86.7 85.6 77.3 83.4 82.9

February 77.6 72.9 65.8 81.2 74.4 74.0

March 86.1 86.2 89.2 85.8 86.8 86.4

April 118.7 121.3 125.6 115.7 120.3 119.7

May 99.7 96.6 99.6 100.3 99.1 98.5

June 92 92 94.4 89.7 92.0 91.6

July 87.5 87 85.5 88.9 87.2 86.8

August 92.9 91.4 93.6 90.2 92.0 91.6

September 99.3 97.3 98.2 100.2 98.8 98.2

October 109.1 105.4 103.2 102.7 105.1 104.6

November 123.6 124.9 126.1 121.6 124.1 123.4

December 150.9 140.1 141.7 139.6 143.1 142.3

Total 1,206.2 1,200.0

c. Interpret the typical seasonal index

April, November and December are the high season and February are the lowest season

Number 28 page 631

The quarterly production of pine lumber, in millions of board feet, by Northwest Lumber

since 2004 is

Year Winter Spring Summer Fall

2004 7.8 10.2 14.7 9.3 2005 6.9 11.6 17.5 9.3 2006 8.9 9.7 15.3 10.1 2007 10.7 12.4 16.8 10.7 2008 9.2 13.6 17.1 10.3

a. Determine the typical seasonal pattern for the production data using the ratio-

moving average

[Type text]

Year Month Production

(thousands)

Four

Quarter

Total

Four Quarter

Moving

average

Centre

Moving

Average

Spesific

Seasonal

2004

Winter 7.8

Spring 10.2

42 10.500

Summer 14.7 10.388 1.415

41.1 10.275

Fall 9.3 10.450 0.890

42.5 10.625

2005

Winter 6.9 10.975 0.629

45.3 11.325

Spring 11.6 11.325 1.024

45.3 11.325

Summer 17.5 11.575 1.512

47.3 11.825

Fall 9.3 11.588 0.803

45.4 11.350

2006

Winter 8.9 11.075 0.804

43.2 10.800

Spring 9.7 10.900 0.890

44 11.000

Summer 15.3 11.225 1.363

45.8 11.450

Fall 10.1 11.788 0.857

48.5 12.125

2007

Winter 10.7 12.313 0.869

50 12.500

Spring 12.4 12.575 0.986

50.6 12.650

Summer 16.8 12.463 1.348

49.1 12.275

Fall 10.7 12.425 0.861

50.3 12.575

2008

Winter 9.2 12.613 0.729

50.6 12.650

Spring 13.6 12.600 1.079

50.2 12.550

Summer 17.1

Fall 10.3

[Type text]

Year Winter Spring Summer Fall

2004 1.415 0.890 2005 0.629 1.024 1.512 0.803 2006 0.804 0.890 1.363 0.857 2007 0.869 0.986 1.348 0.861 2008 0.729 1.079 Average 0.758 0.995 1.410 0.853 Adjusted 0.755 0.991 1.404 0.849

b. Interpret the pattern

Demand and production pine lumber will be high at Summer.

c. Deseasonalize the data and determine the linear trend equation

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� ��� ��.��.���� ���.���

� �� ������� � 0.14 (see Table below)

� �232.155 � 0.14�210�

20� 10.11

Year Month Production

(thousands) Index

Deseasonalized

Production (Y) Code (t) Yt t^2

2004

Winter 7.8 0.755 10.331 1 10.331 1

Spring 10.2 0.991 10.293 2 20.585 4

Summer 14.7 1.404 10.470 3 31.410 9

Fall 9.3 0.849 10.954 4 43.816 16

2005

Winter 6.9 0.755 9.139 5 45.695 25

Spring 11.6 0.991 11.705 6 70.232 36

Summer 17.5 1.404 12.464 7 87.251 49

Fall 9.3 0.849 10.954 8 87.633 64

2006

Winter 8.9 0.755 11.788 9 106.093 81

Spring 9.7 0.991 9.788 10 97.881 100

Summer 15.3 1.404 10.897 11 119.872 121

Fall 10.1 0.849 11.896 12 142.756 144

2007

Winter 10.7 0.755 14.172 13 184.238 169

Spring 12.4 0.991 12.513 14 175.177 196

Summer 16.8 1.404 11.966 15 179.487 225

Fall 10.7 0.849 12.603 16 201.649 256

2008

Winter 9.2 0.755 12.185 17 207.152 289

Spring 13.6 0.991 13.724 18 247.023 324

Summer 17.1 1.404 12.179 19 231.410 361

Fall 10.3 0.849 12.132 20 242.638 400

Toatl 232.155 210 2,532.331 2870

[Type text]

�� � 10.11 � 0.14 �

d. Project the seasonally adjusted production for the four quarter of 2009

������ ��� !" � 10.11 � 0.14 �21� � 13.1 # 0.755 � 9.8

������ '("��) � 10.11 � 0.14 �22� � 13.2 # 0.991 � 13.13

������ '*++!" � 10.11 � 0.14 �23� � 13.4 # 1.404 � 19.79

������ ,-.. � 10.11 � 0.14 �24� � 13.5 # 0.849 � 11.48

Number 29 page 631

Work Gloves Corp, is reviewing its quarterly sales of Touhie, the most durable glove it

produce. The number of pairs produced (in thousand) by quarter are

Year I II III IV

1999 142 312 488 208 2000 146 318 512 212 2001 160 330 602 187 2002 158 338 572 176 2003 162 380 563 200 2004 162 362 587 205

a. Using the ratio-to-moving-average method, determine the four quarterly indexes

See Table below

Year Winter Spring Summer Fall

1999 1.694 0.719 2000 0.498 1.073 1.714 0.702 2001 0.508 1.022 1.884 0.584 2002 0.498 1.082 1.836 0.555 2003 0.504 1.176 1.726 0.617 2004 0.499 1.102 Average 0.5014 1.0909 1.7709 1.6354 Adjusted 0.5016 1.0913 1.7715 1.6356

b. Interpret the typical seasonal pattern

The production in the third quarter is 77.15% above the normal production and in the

first quarter is 49,64% below the normal production

[Type text]

Year Month Production

(thousands)

Four

Quarter

Total

Four

Quarter

Moving

average

Centre

Moving

Average

Spesific

Seasonal

1999

Winter 142

Spring 312

1150 287.500

Summer 488 288.000 1.694

1154 288.500

Fall 208 289.250 0.719

1160 290.000

2000

Winter 146 293.000 0.498

1184 296.000

Spring 318 296.500 1.073

1188 297.000

Summer 512 298.750 1.714

1202 300.500

Fall 212 302.000 0.702

1214 303.500

2001

Winter 160 314.750 0.508

1304 326.000

Spring 330 322.875 1.022

1279 319.750

Summer 602 319.500 1.884

1277 319.250

Fall 187 320.250 0.584

1285 321.250

2002

Winter 158 317.500 0.498

1255 313.750

Spring 338 312.375 1.082

1244 311.000

Summer 572 311.500 1.836

1248 312.000

Fall 176 317.250 0.555

1290 322.500

2003

Winter 162 321.375 0.504

1281 320.250

Spring 380 323.250 1.176

1305 326.250

Summer 563 326.250 1.726

1305 326.250

Fall 200 324.000 0.617

1287 321.750

2004

Winter 162 163.875 0.989

1311 327.750

Spring 362 328.375 1.102

1316 329.000

Summer 587

Fall 205

[Type text]

Number 30 page 631

Sales of roof material, by quarter, sice 2000 by Carolina Home construction, Inc., are

shown below (in $000)

Year I II III IV

2000 210 180 60 246 2001 214 216 82 230 2002 246 228 91 280 2003 258 250 113 298 2004 249 267 116 304 2005 302 290 114 310 2006 321 291 120 320

a. Determine the typical seasonal patterns for sales using he ratio-moving average

method

Year Month Production

(thousands)

Four

Quarter

Total

Four Quarter

Moving average

Centre

Moving

Average

Spesific

Seasonal

2000

i 210

ii 180

696 174.000

iii 60 174.500 0.344

700 175.000

iv 246 179.500 1.370

736 184.000

2001

i 214 186.750 1.146

758 189.500

ii 216 187.500 1.152

742 185.500

iii 82 189.500 0.433

774 193.500

iv 230 195.000 1.179

786 196.500

2002

i 246 197.625 1.245

795 198.750

ii 228 205.000 1.112

845 211.250

iii 91 212.750 0.428

857 214.250

iv 280 217.000 1.290

879 219.750

2003

i 258 222.500 1.160

901 225.250

ii 250 227.500 1.099

919 229.750

iii 113 232.375 0.486

940 235.000

iv 298 237.125 1.257

957 239.250

[Type text]

Year Month Production

(thousands)

Four

Quarter

Total

Four Quarter

Moving average

Centre

Moving

Average

Spesific

Seasonal

2004

i 279 239.625 1.164

960 240.000

ii 267 240.750 1.109

966 241.500

iii 116 244.375 0.475

989 247.250

iv 304 250.125 1.215

1012 253.000

2005

i 302 267.250 1.130

1126 281.500

ii 290 267.750 1.083

1016 254.000

iii 114 256.375 0.445

1035 258.750

iv 310 258.875 1.197

1036 259.000

2006

i 321 130.250 2.464

1042 260.500

ii 291 300.500 0.968

1362 340.500

iii 120

iv 320

2000 2001 2002 2003 2004 2005 2006 Average Adjusment

I 1.146 1.245 1.160 1.164 1.130 2.464 1.385 1.332

II 1.152 1.112 1.099 1.109 1.083 0.968 1.087 1.046

III 0.344 0.433 0.428 0.486 0.475 0.445 0.435 0.418

IV 1.370 1.179 1.290 1.257 1.215 1.197 1.252 1.204

4.159 4.000

b. Deseasonalize the data and determine the trend equation

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� �28 �48.078.080� � �210��4.230.148�

28�2870� � �210��� 12.63

� � 4.230.148 � 12.63�210�

28� 56.37

�� � 56.37 � 12.63 �

[Type text]

Year Quarter Sales

($000) Index

Deseasonalized

Production (Y) Code (t) Yt t^2

2000

I 210 1.332 158 1 158 1

II 180 1.046 172 2 344 4

III 60 0.418 144 3 431 9

IV 246 1.204 204 4 817 16

2001

I 214 1.332 161 5 803 25

II 216 1.046 207 6 1,239 36

III 82 0.418 196 7 1,373 49

IV 230 1.204 191 8 1,528 64

2002

I 246 1.332 185 9 1,662 81

II 228 1.046 218 10 2,180 100

III 91 0.418 218 11 2,395 121

IV 280 1.204 233 12 2,791 144

2003

I 258 1.332 194 13 2,518 169

II 250 1.046 239 14 3,346 196

III 113 0.418 270 15 4,055 225

IV 298 1.204 248 16 3,960 256

2004

I 279 1.332 209 17 3,561 289

II 267 1.046 255 18 4,595 324

III 116 0.418 278 19 5,273 361

IV 304 1.204 252 20 5,050 400

2005

I 302 1.332 227 21 4,761 441

II 290 1.046 277 22 6,099 484

III 114 0.418 273 23 6,273 529

IV 310 1.204 257 24 6,179 576

2006

I 321 1.332 241 25 6,025 625

II 291 1.046 278 26 7,233 676

III 120 0.418 287 27 7,751 729

IV 320 1.204 266 28 7,442 784

Total 4,230.148 210 48,078.080 2870

c. Project the sales 2007 and then seasonally adjust each quarter

������,1*-" !" � 56.37 � 12.63 �29� � 422.55 # 1.332 � 562

������,1*-" !" � � 56.37 � 12.63 �30� � 435.18 # 1.046 � 455

������,1*-" !" � 56.37 � 12.63 �31� � 447.81 # 0.418 � 187

������,1*-" !" 2 � 56.37 � 12.63 �32� � 460.44 # 1.204 � 554

[Type text]