1 HAMS Technologies www.hams.co.in director@hams.co.in priyank@hams.co.in vivek@hams.co.in HAMS Technologies There is a very special property of all linear regression model that if the summation of all the independent variable is constant then dependent variable grow fastest only if Ratio of independent variable is equal to ratio of exponential respective model coefficient. or we can Ratio of model is same as ration of logarithmic respective independent variable value 2 HAMS Technologies Mathematically .. Given a regression model y 1 x1 2 x2 3 x3 ...... n xn also given, x1 x2 x3 ......xn K cons Then y grow faster only if x1 / x2 e1 / e 2 or say 1 / 2 log( x1 ) / log( x2 ) 1 2 3 4 n R A M1 M 2 M3 M 4 M n HAMS Technologies 3 Lets prove this… Given Regression model is y 1 x1 2 x2 3 x3 ...... n xn now consider y log( R), x1 log(M 1 ), x2 log(M 2 )......xn log(M n ) Then original regress model will be log( R) 1 log(M 1 ) 2 log(M 2 )...... n log(M n ) log( R) log(M 11 M 2 2 M 3 3 M 4 4 M n n ) R M 11 M 2 2 M 3 3 M 4 4 M n n now Normalize this equation w.r.t M HAMS Technologies 4 M n n M 1 1 M 2 2 R ( ) .( ) ( ) * M i i Mi Mi Mi 1. This factor will remain constant for given problem 2. So the growth of R will be directly proportional to this factor, For further derivation consider the number of independent drivers are two , n=2. We can use same approach for large n R ( M1 M2 )1 .( ) 2 M1 M 2 M1 M 2 5 HAMS Technologies 1 0.9, 2 0.1 M1 M2 R( ) 1 * ( ) 2 M1 M 2 M1 M 2 x M1 / M 2 R R( 1 1 1 ) 1 * ( x 1 x 1 ) 2 f ( x ) 1 1 R ( ) 1 * ( ) 2 0 x x 1 1 1 x 1 ( 1 2 0.5 1 0.1, 2 0.9 x 1 1 1 1 x 1 1 x 1 ) *( )2 * ( ) 2 ( ) * 2 ( ) 2 1 * ( 1) * ( )2 0 1 x 1 x 1 x 1 x 1 x 1 x 1 / 2 x M 1 / M 2 6 HAMS Technologies So, 1 / 2 x M 1 / M 2 log( x1 ) / log( x2 ) Ratio of model is same as ratio of logarithmic respective independent variable value or x1 / x2 e1 / e 2 Ratio of independent variable is equal to ratio of exponential respective model coefficient. hence proved .. 7 HAMS Technologies Thank you Kindly drop us a mail at below mention address for any suggestion and clarification. We like to hear from you HAMS Technologies www.hams.co.in director@hams.co.in priyank@hams.co.in vivek@hams.co.in 8 HAMS Technologies