6-18
k Logarithmic Regression Graph
  Logarithmic regression expresses  y  as a logarithmic function of  x . The standard logarithmic 
regression formula is  y  =  a  +  b  × In  x , so if we say that X = In  x , the formula corresponds to 
linear regression formula  y  =  a  +  b X.
  
       1(CALC) 6( g) 2(Log) 
       6(DRAW)
  
  The following is the logarithmic regression model formula.
   y   =  a  +  b ·ln  x 
   a  
 ..............regression constant term
   b   .............. regression coefficient
k Exponential Regression Graph
  Exponential regression expresses  y  as a proportion of the exponential function of  x . The 
standard exponential regression formula is  y  =  a  ×  e  
bx 
, so if we take the logarithms of both 
sides we get In  y  = In  a  +  bx . Next, if we say Y = In  y , and A = In  a , the formula corresponds to 
linear regression formula Y = A +  bx .
  
        1(CALC) 6( g) 3(EXP) 
        1( ae
bx
 ) or  2( ab
x
 )
        6(DRAW)
  
  The following is the exponential regression model formula.
   y   =  a · e  
bx 
   a   ..............regression  coefficient
   b   ..............regression constant term
  
   y   =  a · b  
x 
   a   ..............regression constant term
   b   ..............regression  coefficient