# Example 12 (a) - Straight line fit to BOD data
# BOD = a0 + a1*Time
# Verified Solution: a0 = 0.657797, a1 = 0.178056
[
t B
1 0.6
2 0.7
4 1.5
6 1.9
8 2.1
10 2.6
12 2.9
14 3.7
16 3.5
18 3.7
20 3.8
]
# polyfit <x> <y> <order> [origin]
polyfit t B 1
B = a0 + a1t
| Variable |
Value |
95% confidence |
| a0 |
0.65779698 |
0.37489555 |
| a1 |
0.17805616 |
0.03167417 |
| R^2 |
R^2adj |
Rmsd |
Variance |
| 0.9472735 |
0.941415 |
0.0783494 |
0.0825304 |
Polynomial Regression Plot for order 1

Residuals Plot for Polynomial of order 1

Source data points and calculated data points
| |
t |
B |
B calc |
Delta B |
| 1 |
1 |
0.6 |
0.83585313 |
-0.23585313 |
| 2 |
2 |
0.7 |
1.0139093 |
-0.31390929 |
| 3 |
4 |
1.5 |
1.3700216 |
0.1299784 |
| 4 |
6 |
1.9 |
1.7261339 |
0.17386609 |
| 5 |
8 |
2.1 |
2.0822462 |
0.01775378 |
| 6 |
10 |
2.6 |
2.4383585 |
0.16164147 |
| 7 |
12 |
2.9 |
2.7944708 |
0.10552916 |
| 8 |
14 |
3.7 |
3.1505832 |
0.54941685 |
| 9 |
16 |
3.5 |
3.5066955 |
-0.00669546 |
| 10 |
18 |
3.7 |
3.8628078 |
-0.16280778 |
| 11 |
20 |
3.8 |
4.2189201 |
-0.41892009 |
General
Regression including a free parameter
Number of observations = 11