Texas Instruments BA-20 Profit Manager User Manual - Page 69

Regression Models, Analyzing One-Variable Statistics, Computing Values Automatically

Page 69 highlights

• When you enter data for one-variable statistics, Xnn represents the value and Ynn specifies the number of occurrences (frequency). • When you enter a value for Xnn, the value for Ynn defaults to 1. Analyzing One-Variable Statistics To analyze one-variable statistics, select 1-V. Only values for n, v, Sx, sX, GX, and GX2 are computed and displayed for one-variable statistics. Analyzing Two-Variable Statistics You can choose from among these four regression-analysis methods: • LIN • Ln • EXP • PWR Computing Values Automatically Except for the predicted X' and Y' values, the calculator computes and displays values for statistics variables automatically when you access them. Using X' and Y' for Regression Predictions To use the X' and Y' variables for regression predictions, you either can enter a value for X' to compute Y' or enter a value for Y' to compute X'. Regression Models For two-variable data, the Statistics worksheet uses four regression models for curve fitting and forecasting. Model LIN Ln EXP PWR Formula Y = a + b X Y = a + b ln(X) Y = a bx Y = a Xb Restrictions None All X values > zero All Y values > zero All X and Y values > zero The calculator interprets the X value as the independent variable and the Y value as the dependent variable. The calculator computes the statistical results using these transformed values: • LIN uses X and Y. Statistics Worksheet 65

  • 1
  • 2
  • 3
  • 4
  • 5
  • 6
  • 7
  • 8
  • 9
  • 10
  • 11
  • 12
  • 13
  • 14
  • 15
  • 16
  • 17
  • 18
  • 19
  • 20
  • 21
  • 22
  • 23
  • 24
  • 25
  • 26
  • 27
  • 28
  • 29
  • 30
  • 31
  • 32
  • 33
  • 34
  • 35
  • 36
  • 37
  • 38
  • 39
  • 40
  • 41
  • 42
  • 43
  • 44
  • 45
  • 46
  • 47
  • 48
  • 49
  • 50
  • 51
  • 52
  • 53
  • 54
  • 55
  • 56
  • 57
  • 58
  • 59
  • 60
  • 61
  • 62
  • 63
  • 64
  • 65
  • 66
  • 67
  • 68
  • 69
  • 70
  • 71
  • 72
  • 73
  • 74
  • 75
  • 76
  • 77
  • 78
  • 79
  • 80
  • 81
  • 82
  • 83
  • 84
  • 85
  • 86
  • 87
  • 88
  • 89
  • 90
  • 91
  • 92
  • 93
  • 94
  • 95
  • 96
  • 97
  • 98
  • 99
  • 100
  • 101
  • 102
  • 103
  • 104
  • 105
  • 106
  • 107
  • 108
  • 109
  • 110
  • 111
  • 112
  • 113
  • 114

Statistics Worksheet
65
When you enter data for one-variable statistics,
X
nn
represents the
value and
Y
nn
specifies the number of occurrences (frequency).
When you enter a value for
X
nn
, the value for
Y
nn
defaults to 1.
Analyzing One-Variable Statistics
To analyze one-variable statistics, select
1-V
. Only values for
n
,
v
,
Sx
,
s
X
,
G
X
, and
G
X
2
are computed and displayed for one-variable statistics.
Analyzing Two-Variable Statistics
You can choose from among these four regression-analysis methods:
LIN
Ln
EXP
PWR
Computing Values Automatically
Except for the predicted
X'
and
Y'
values, the calculator computes and
displays values for statistics variables automatically when you access
them.
Using X' and Y' for Regression Predictions
To use the
X'
and
Y'
variables for regression predictions, you either can
enter a value for
X'
to compute
Y'
or enter a value for
Y'
to compute
X'
.
Regression Models
For two-variable data, the Statistics worksheet uses four regression
models for curve fitting and forecasting.
The calculator interprets the
X
value as the independent variable and the
Y
value as the dependent variable.
The calculator computes the statistical results using these transformed
values:
LIN
uses X and Y.
Model
Formula
Restrictions
LIN
Y = a + b X
None
Ln
Y = a + b ln(X)
All X values > zero
EXP
Y = a b
x
All Y values > zero
PWR
Y = a X
b
All X and Y values > zero