HP 49g+ - Manual (Page 585)

Page 18-18
The FIT sub-menu
The FIT sub-menu contains functions used to fit equations to the data in
columns Xcol and Ycol of the
ΣDATA matrix.
The functions available in this sub-menu are:
ΣLINE: provides the equation corresponding to the most recent fitting.
LR: provides intercept and slope of most recent fitting.
PREDX: used as y
@PREDX, given y find x for the fitting y = f(x).
PREDY: used as x @PREDY, given x find y for the fitting y = f(x).
CORR: provides the correlation coefficient for the most recent fitting.
COV: provides sample co-variance for the most recent fitting
PCOV: shows population co-variance for the most recent fitting.
The SUMS sub-menu
The SUMS sub-menu contains functions used to obtain summary statistics of
the data in columns Xcol and Ycol of the
ΣDATA matrix.
ΣX : provides the sum of values in Xcol column.
ΣY : provides the sum of values in Ycol column.
ΣX^2 : provides the sum of squares of values in Xcol column.
ΣY^2 : provides the sum of squares of values in Ycol column.
ΣX*Y: provides the sum of x⋅y, i.e., the products of data in columns Xcol and
Ycol.
N
Σ : provides the number of columns in the ΣDATA matrix.
Example of STAT menu operations
Let ΣDATA be the matrix shown in next page.
• Type the matrix in level 1 of the stack by using the Matrix Writer.
• To store the matrix into ΣDATA, use: @)DATA „ @£DAT