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PLS

Syntax: PLS(X, Y, N)

X = a range representing a row or column vector of independent variable values
Y = a range representing a row or column vector of dependent variable values
N = polynomial degree (in the range 1 to 10)

PLS analyzes the least squares polynomial model. Given the Nth degree polynomial model:

\begin{displaymath}
y = a_N x^N + a_{N-1} x^{N-1} + \cdots + a_0    ,
\end{displaymath}

the format of the table produced by PLS is:

\begin{displaymath}
\begin{array}{ccccc}
\hat{a}_n & \hat{a}_{n-1} & \cdots & \h...
...a}_{n-1}}) & \cdots & p(t_{\hat{a}_0}) & p(t_R) \\
\end{array}\end{displaymath}

The table produced by this function is identical to that of LLS, with the polynomial coefficients listed in order of decreasing degree.

Example:

Matrix A1..C4 =

  A B C
1 0 0 1
2 1 1 1
3 4 2 1
4 9 3 1
       

Matrix D1..D4 =

  D
1 3
2 5
3 11
4 18
   

PLS(B1..B4, D1..D4, 2) =
1.25 1.35 2.85 0.45
0.34 1.05 0.65 1.00
3.73 1.29 4.36 151.44
0.17 0.42 0.14 0.06

The above result displays only 2 decimal places and is exactly equivalent to LLS(A1..C4, D1..D4)

Excel function: N/A


next up previous contents index
Next: PMT Up: A. Function Reference Previous: PI   Contents   Index
SpreadScript User's Guide, Version 1.2
Grey Trout Software
02 March 2003