THE FLORIDA STATE UNIVERSITY ARTS AND SCIENCES ...

R
dn
= 1.60 ∗Temperatur
e ( ° C) + 0.05 ∗ WFP (%) - 14.25 ∗ OC (%)
- 56.70
∗
pH
+ 471.74 (R
2
- 0.04 *
= 0.
69).
Nitrate
Concentrat ion
121
(
-1
μ g N g soil) -----
Table 4.3 Texture 1, Linear multi-regression with all variables.
Equation 4.3
Coefficients Estimate Std.Error t-value Significance
Intercept 5380.46 3257.95 1.65 *
Bulk Density (g cm-3) 1.60 0.62 2.57
NO3- Conc ( µg N g-1 soil) -0.03 0.11 -0.22
OC (%) -246.08 148.87 -1.65
pH -460.04 269.77 -1.71
Soil Depth (cm) -970.55 631.33 -1.54
Temp (ºC) 0.92 1.18 0.78
WFP (%) -0.80 0.50 -1.59
Signif.Codes Signif.Codes
0 '***' 0.001 '**'
0.01 '*' 0.05 '.'
0.1 1
Table 4.4 Texture 1, Linear multi-regression with selected variables (S)
Coefficients Estimate Std.Error t-value Significance
(Intercept) 471.74 99.2113 4.75 ***
NO3 - Conc ( µg N g -1 soil) -0.04 0.0256 -1.56
OC (%) -14.25 7.0945 -2.01 .
pH -56.70 11.0461 -5.13 ***
Temp (ºC) 1.61 0.6657 2.42 *
WFP (%) 0.05 0.1125 0.4
Signif.Codes Signif.Codes Signif.Codes
0 '***' 0.001 '**' 0.01
0.01 '*' 0.05 '.' 0.1
0.1 1
The two developed equations are applied to the test dataset and the results of the
predictions are shown here. The error is extremely large in both cases and the reliability
of the predicative equation is objectionable.