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
Σ
DATA matrix.
The functions available in this sub-menu are:
Σ
LINE: 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
Σ
DATA matrix.
Σ
X : provides the sum of values in Xcol column.
Σ
Y : provides the sum of values in Ycol column.
Σ
X^2 : provides the sum of squares of values in Xcol column.
Σ
Y^2 : provides the sum of squares of values in Ycol column.
Σ
X*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
Σ
DATA matrix.
Example of STAT menu operations
Let
Σ
DATA 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
Σ
DATA, use:
@)DATA
„
@£DAT