Tuesday, 25 December 2012

MODEFICATION OF THE CENTRAL PREDICTION THEORY



HISTORICAL BACKGROUND

The term “ regression” was named by Francis Galton in nineteenth century to describe a biological phenomenon. The phenomenon was that the hights of descendants of tall ancestors tend to regress down towards a normal average(a phenomenon also known as regression towards the mean).
For Galton regression had only this biological meaning, but his work was later extended by Udny Yule and Karl Pearson to a more general statistical context. In the work of Yule and Pearson the joint distribution of the response and explanatory variables is assumed to be Gaussian (i.e the earliest form of regression was the method of least squares which was published by Legendre in 1805 and by gauss in 1809). This assumption was weakened by R.F fisher in his works of 1922 and 1925. Fisher assumed that the conditional distribution of the response variable is Gaussian , but the joint distribution need not be in respect , fisher’s assumption is closer to Gauss’s formulation of 1821. In the year 2007, I was able to formulate a concept call Equal Paring Concept in which we can determine the central point of the ordered pair ( ×, y) of a straight line equations. This concept was later translated by me in the year 2010 as Gravitational (Central) Point Values Theory of a straight line equation.
This theorem states that at central point in the ordered pair ( × ,y),  ×  is adding itself to infinity when  y  is subtracting itself to infinity and vice-versal.
This concept was later applied in statistical form of analysis which I named Central Prediction (Regression) Theory in which we can predict the mean value of one or more variables if the mean value of only one variable is known . This concept is total different from the Galton’s or Gaussian's concept and proved useful and accurate than theirs. Below is the continuous development of the Central Regression Theory. 







PREDICTING TWO VARIABLES FROM ONE VARIABLE

 For apparent relationship between three variables, the central pair equations are given as;
Ym=K1Xm +C……….(1)
Zm=K1Xm+K2Ym +C…..(2)

Where;

K1=ΣY/2ΣX

K2=[ΣXΣZ-ΣXΣX]/ΣxΣy

C=ΣY/2N



The table below contained the apparent relationship between three variables (i.e inflation rate, market price and profit earned ) from the year 2000 to 2009 for certain business corporation in million of cedis.
                                
Year        
inflation rate(×%)                
market price(z-cedis)
profit earned(y-cedis)
2000
24
80
35
2001
28
85
39
200
33
88
41
2003
31
90
29
2004
37
95
40
2005
30
92
28
2006
25
82
20
2007
23
75
19
2008
28
78
24
2009
31
85
30

From the table above we know mean inflation rate of the existing data from 2000-2009 to be 29%. Empirical speaking, the inflation rate to continuous years from 2009 may vary from year to year and the mean –inflation rate may change to continuous years from 2009 and the mean-market price and mean-profit earned may change with changing mean-inflation rates to continuous years from 2009.




Example.
If the mean- inflation rate is 26% for the year 2000 to 2012; find the best estimate of the corporation market price and profit to be earned .


Solution


 Ym=K1Xm +C

K1=0.526

C=15.25

Ym=0.526(26) + 15.25

Ym=28.93

Hence, the men-profit earned is 28.93million cedis.


Also;


Zm=K1Xm +K2Ym +C

K2=1.79

Zm=0.53(26) + 1.79(28.93) +15.25

Zm=80.62

Hence, the mean-market price is 80.62million cedis.





REFERENCE
Galton, Francis.(1886). 'Regression Towards Mediocrity in Hereditary Stature'. Volume 15.


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