Quarterly house sales data for time span from the starting of 2005 until the middle of 2010 were investigated by time-series methods. Autocorrelation and partial autocorrelation purposes were calculated for the data. Appropriate Box-Jenkins autoregressive incorporated going mean model was fitted. Validity of the model was checked utilising benchmark statistical techniques. The forecasting power of autoregressive incorporated going mean model was utilised to forecast house sales for three premier years.
Sales are the lifeblood of a business. It's what assists businesses to yield workers, cover functioning costs, purchase more inventory, market new goods and appeal more investors. Sales forecasting is a vital part of the economic designing of a business. It's a self-assessment device that values past and present sales statistics to intelligently forecast future performance.
Data set of Scooter Production
Trend of data
Seasonal Decomposition
Series Name:Scooter
Case Number
Original Series
Moving Average Series
Ratio of initial sequence to moving Average (%)
Seasonal Factor (%)
Seasonally Adjusted Series
Smoothed Trend-Cycle Series
Irregular (Error) Component
1
3361.000
.
.
120.7
2785.047
2781.724
1.001
2
2822.000
.
.
103.1
2737.978
2767.806
.989
3
2268.000
2754.5000
82.3
81.6
2780.392
2739.970
1.015
4
2567.000
2709.2500
94.7
94.7
2711.243
2698.697
1.005
5
3180.000
2670.0000
119.1
120.7
2635.064
2658.869
.991
6
2665.000
2643.5000
100.8
103.1
2585.652
2620.867
.987
7
2162.000
2605.0000
83.0
81.6
2650.444
2594.710
1.021
8
2413.000
2563.5000
94.1
94.7
2548.589
2553.987
.998
9
3014.000
2530.7500
119.1
120.7
2497.510
2504.631
.997
10
2534.000
2476.5000
102.3
103.1
2458.553
2448.095
1.004
11
1945.000
2428.2500
80.1
81.6
2384.419
2399.438
.994
12
2220.000
2380.0000
93.3
94.7
2344.745
2359.150
.994
13
2821.000
2338.0000
120.7
120.7
2337.584
2323.897
1.006
14
2366.000
2308.0000
102.5
103.1
2295.555
2281.641
1.006
15
1825.000
2262.7500
80.7
81.6
2237.308
2237.447
1.000
16
2039.000
2218.0000
91.9
94.7
2153.574
2192.258
.982
17
2642.000
2173.0000
121.6
120.7
2189.258
2155.433
1.016
18
2186.000
2133.7500
102.4
103.1
2120.914
2121.055
1.000
19
1668.000
2122.2500
78.6
81.6
2044.839
2091.092
.978
20
1993.000
2078.5000
95.9
94.7
2104.989
2064.691
1.020
21
2467.000
.
.
120.7
2044.246
2051.491
.996
Model Description
Model Name
MOD_1
Series or Sequence
1
Scooter
Transformation
None
Non-Seasonal Differencing
0
Seasonal Differencing
0
Length of Seasonal Period
4
Horizontal Axis Labels
Date_
Intervention Onsets
None
Reference Lines
None
Area Below the Curve
Not filled
Applying the form specifications from MOD_1
Case Processing Summary
Scooter
Series or Sequence Length
21
Number of Missing places in the Plot
User-Missing
0
System-Missing
0
Above grahs shows seasonality and decreasing trend.
After applying seasonal difference of 4.
Model Description
Model Name
MOD_6
Series or Sequence
1
Scooter
Transformation
None
Non-Seasonal Differencing
0
Seasonal Differencing
4
Length of Seasonal Period
4
Horizontal Axis Labels
Date_
Intervention Onsets
None
Reference Lines
None
Area Below the Curve
Not filled
Applying the form specifications from MOD_6
Case Processing Summary
Scooter
Series or Sequence Length
21
Number of Missing values in the Plot
User-Missing
0
System-Missing
0
Model Description
Model Name
MOD_2
Series Name
1
Scooter
Transformation
None
Non-Seasonal Differencing
0
Seasonal Differencing
4
Length of Seasonal Period
4
Maximum Number of Quarterly differences
16
Process Assumed for Calculating the Standard Errors of the Autocorrelations
Independence(white noise)a
Display and Plot
All quarterly differences
Applying the form specifications from MOD_2
a. Not applicable for calculating the benchmark errors of the partial autocorrelations.
Case Processing Summary
Scooter
Series Length
21
Number of Missing Values
User-Missing
0
System-Missing
0
Number of Valid Values
21
Number of standards Lost Due to Differencing
16
Number of Computable First Quarterly differences After Differencing
4
Autocorrelations
Series:Scooter
Quarterly difference
Autocorrelation
Std. Errora
Box-Ljung Statistic
Value
df
Sig.b
1
-.426
.338
1.587
1
.208
2
-.124
.293
1.765
2
.414
3
.067
.239
1.844
3
.605
a. The underlying process assumed is self-reliance (white noise).
b. Based on the asymptotic chi-square approximation.
Partial Autocorrelations
Series:Scooter
Quarterly difference
Partial Autocorrelation
Std. Error
1
-.426
.447
2
-.373
.447
3
-.232
.447
Regression and Correlation Analysis
Model Summary
Model
R
R Square
Adjusted R Square
Std. Error of the Estimate
1
.677a
.459
.430
334.98500
a. Predictors: (Constant), YEAR, not periodic
ANOVAb
Model
Sum of Squares
df
Mean Square
F
Sig.
1
Regression
1806953.716
1
1806953.716
16.103
.001a
Residual
2132084.093
19
112214.952
Total
3939037.810
20
a. Predictors: (Constant), YEAR, not periodic
b. Dependent Variable: Scooter
Coefficientsa
Model
Unstandardized Coefficients
Standardized Coefficients
t
Sig.
B
Std. Error
Beta
1
(Constant)
380506.411
94215.978
4.039
.001
YEAR, not periodic
-188.318
46.929
-.677
-4.013
.001
a. Dependent Variable: Scooter
Correlations
Scooter
YEAR, not periodic
Scooter
Pearson Correlation
1
-.677**
Sig. (2-tailed)
.001
N
21
21
YEAR, not periodic
Pearson Correlation
-.677**
1
Sig. (2-tailed)
.001
N
21
21
**. Correlation is important at the 0.01 level (2-tailed).
Forecast Values
2499.92
Q3 2010
2779.331
Q4 2010
2044.711
Q1 2011
2296.449
Q2 2011
2510.78
Q3 2011
2803.617
Q4 2011
2061.912
Q1 2012
2306.016
Q2 2012
2520.74
Q3 2012
2823.88
Q4 2012
2097.127
Q1 2013
2318.006
Q2 2013
2532.32
Q3 2013
2849.867
Q4 2013
2116.601
Q1 2014
2329.251
Q2 2014
2543.06
Q3 2014
2877.71
Q4 2014
2142.079
Q1 2015
2332.108
Q2 2015
2553.56
Q3 2015
Manufacturing Cost
Trend of data
Seasonal Decomposition
Series Name:manufactureCost
DATE_
Original Series
Moving Average Series
Ratio of Original Series to Moving Average Series (%)
Seasonal Factor (%)
Seasonally Adjusted Series
Smoothed Trend-Cycle Series
Irregular (Error) Component
Q3 2005
5105.000
.
.
113.8
4487.245
4387.025
1.023
Q4 2005
4583.000
.
.
103.7
4419.790
4319.309
1.023
Q1 2006
3480.000
4273.7500
81.4
85.9
4050.891
4183.875
.968
Q2 2006
3927.000
4148.7500
94.7
96.6
4063.814
4085.366
.995
Q3 2006
4605.000
4029.5000
114.3
113.8
4047.750
3998.323
1.012
Q4 2006
4106.000
3963.5000
103.6
103.7
3959.777
3913.584
1.012
Q1 2007
3216.000
3874.7500
83.0
85.9
3743.582
3794.735
.987
Q2 2007
3572.000
3736.5000
95.6
96.6
3696.446
3693.591
1.001
Q3 2007
4052.000
3638.7500
111.4
113.8
3561.668
3599.339
.990
Q4 2007
3715.000
3566.5000
104.2
103.7
3582.702
3521.294
1.017
Q1 2008
2927.000
3473.0000
84.3
85.9
3407.172
3426.363
.994
Q2 2008
3198.000
3390.0000
94.3
96.6
3309.416
3337.000
.992
Q3 2008
3720.000
3282.5000
113.3
113.8
3269.843
3267.772
1.001
Q4 2008
3285.000
3246.2500
101.2
103.7
3168.015
3211.718
.986
Q1 2009
2782.000
3189.7500
87.2
85.9
3238.385
3156.633
1.026
Q2 2009
2972.000
3095.2500
96.0
96.6
3075.543
3072.905
1.001
Q3 2009
3342.000
3028.2500
110.4
113.8
2937.585
3012.821
.975
Q4 2009
3017.000
2997.2500
100.7
103.7
2909.559
2972.167
.979
Q1 2010
2658.000
2950.5000
90.1
85.9
3094.043
2939.715
1.052
Q2 2010
2785.000
2870.0000
97.0
96.6
2882.028
2876.873
1.002
Q3 2010
3020.000
.
.
113.8
2654.550
2845.453
.933
Model Description
Model Name
MOD_3
Series or Sequence
1
manufactureCost
Transformation
None
Non-Seasonal Differencing
0
Seasonal Differencing
0
Length of Seasonal Period
4
Horizontal Axis Labels
Date_
Intervention Onsets
None
Reference Lines
None
Area Below the Curve
Not filled
Applying the form specifications from MOD_3
Case Processing Summary
manufactureCost
Series or Sequence Length
21
Number of Missing Values in the Plot
User-Missing
0
System-Missing
0
Above grahs shows seasonality and decreasing trend.