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