Table 2 The mean value standard error and its statistical significance for the cubic mixed-temporal-effect model + EW density (random temporal effects and fixed EW density effects) and for the cubic fixed-temporal-effect model + EW density. The equation of the model is as follows: Ln (CO2EW/CO2CTL) = a + bxTime + cxEW_Density + dxTime2 + exTime3 + fx(Time/EW_Density).
Value | Std error | DF | t-value | p-value | |
|---|---|---|---|---|---|
Cubic time random-effect + EW density fixed-effect model | |||||
a: Intercept | 0.1828 | 0.0458 | 500 | 3.99 | 0.0001 |
b: Time | 0.00017 | 0.00044 | 500 | 2.09 | 0.0371 |
c: density | 0.003649 | 0.00071 | 40 | 5.09 | 0.00001 |
d: Time2 | − 6.81E−6 | 1.90E−6 | 500 | − 3.91 | 0.0001 |
e: Time3 | 1.17E−08 | 3.41E−09 | 500 | 3.64 | 0.0003 |
f: Time/density | 0.00022 | 0.00001 | 500 | 9.62 | 2.37E−6 |
Cubic time fixed-effect + EW density fixed-effect model | |||||
a: Intercept | 0.22 | 0.0265 | 500 | 9.69 | < 2E−16 |
b: Time | − 0.000919 | 0.000794 | 500 | − 1.101 | 0.242 |
c: Density | 0.00359 | 3.64E−4 | 40 | 9.839 | < 2E−16 |
d: Time2 | − 4.13E−6 | − 6.06E−6 | 500 | − 0.131 | 0.496 |
e: Time3 | 1.09E−08 | 1.202E−08 | 500 | 0.377 | 0.363 |
f: Time/density | 0.0046 | 0.000227 | 500 | 20.408 | 0.000274 |
