Manuals/calci/LOGEST

LOGEST (YRange,XRange,Constant,Stats)


where,

  • is a set of Y values,
  • is an optional set of X values,
  • is a logical value TRUE or FALSE, that decides whether to force the constant 'b' to 1,
  • is a logical value TRUE or FALSE, that decides whether to return additional regression statistics.
    • LOGEST() is an array function that calculates the exponential curve that fits the data values and returns an array of values that describes the curve.

Description

  • If 'YRange' is the set of dependent variable, 'XRange' is the set of independent variable, 'm' is a constant base for X value and 'b' is constant (Y-intercept),

then equation for curve is -

 
  • For multiple ranges of X-values,
 
  • Argument values   and   should be numeric, else Calci displays NaN error message.
  • The length of array of XRange values should be equal to length of array of YRange values, else Calci displays #NULL error message.
  •   is a logical value that decides whether to make constant 'b' equal to 1.
  • If   = TRUE or omitted, 'b' is calculated normally. If   = FALSE, 'b' is made equal to 1.
  •   is a logical value that decides whether to display additional regression statistics.
  • If   = TRUE, calci returns additional regresstion statistics. If   = FALSE or omitted, Calci returns the values of 'm coefficients' and the constant 'b'.
  • When there is only one independent X variable, Y intercept (b) can be calculated using following formulas -
 
  • The additional regression is displayed in the following format where each statistic value is described as below-
    ---    
    ---    
   
   
   
  •   is an array of constant base values for curve equation
  •   is the constant value of Y when X=0
  •   is the standard error value for m1
  •   is the standard error value for constant b
  •   is the coefficient of determination
  •   is the standard error value for Y estimate
  •   is the observed F value
  •   is the number of degrees of freedom
  •   is the regression sum of squares
  •   is the residual sum of squares

Examples

X1 values X2 values Y values
1 15 5
2 17 9
3 23 11
4 28 16
5 30 20

Example 1: With single range of X values -

=LOGEST(C2:C6,A2:A6,TRUE,TRUE)  : Displays all the regression statistics for curve 
with Y values in cells C2 to C6 and X values in cells A2 to A6.
1.3976542375431584 4.015612511401349
0.035964826100314505 0.11928183382512401
0.9665390759484563 0.11373076612886521
86.65681866342828 3
1.1208788400613339 0.038804061492775904


Example 2: With multiple range of X values -

=LOGEST(C2:C6,A2:B6,TRUE,TRUE) : Displays all the regression statistics for curve 
with Y values in cells C2 to C6 and X values in cells A2 to B6.
0.9684996526566505 1.593646236498643
0.05737674420683413 0.23878654115432985
0.9710443899207976 0.12957493182116453
33.53562184546261 2
1.1261035756411908 0.03357932591291887

Related Videos

LOGEST

See Also

References