Table 7 Relationship between drying rate and factors for Douglas-fir at different MC levels

Layer-2

− 0.634¹

(0.456)²

− 4.448**

(1.993)

− 1.132

(0.798)

− 1.053

(0.773)

− 0.205

(0.368)

0.318

(0.249)

0.780***

(0.155)

Layer-3

− 0.396

(0.462)

− 3.926**

(1.765)

0.108

(0.911)

− 0.242

(0.818)

− 0.099

(0.378)

0.105

(0.290)

1.480***

(0.155)

Layer-4

− 0.939**

(0.458)

− 6.092***

(1.738)

− 1.103

(0.979)

− 1.360

(0.827)

− 0.521

(0.387)

− 0.211

(0.274)

1.333***

(0.179)

Layer-5

− 1.083**

(0.474)

− 5.611***

(1.692)

− 1.136

(0.979)

− 0.677

(0.853)

− 0.409

0.040

(0.321)

1.400***

(0.269)

Layer-6

− 1.595***

(0.462)

− 7.248***

(1.738)

− 1.272

− 1.723**

(0.830)

− 0.929**

(0.439)

− 0.506

(0.317)

Layer-7

− 1.561***

(0.480)

− 5.082***

(1.710)

− 1.171

(0.848)

− 1.570

− 1.369***

(0.439)

− 0.495

(0.350)

Layer-8

− 2.124***

(0.464)

− 7.744***

(1.741)

− 1.270

− 2.417***

(0.853)

− 1.883***

(0.422)

− 0.955**

(0.350)

Layer-9

− 2.829***

(0.482)

− 7.319***

(1.702)

− 2.666***

(0.868)

− 3.557*** (0.853)

− 2.458***

(0.503)

− 1.185***

(0.415)

Layer-10

− 4.716***

(0.482)

− 11.923***

(1.661)

− 4.027***

(1.049)

− 4.196***

(1.155)

− 3.257***

(0.600)

MC

0.252***

(0.016)

Drying time

1.395***

(0.102)

2.632***

(0.307)

1.374***

(0.271)

1.469***

(0.290)

1.331***

(0.188)

0.573**

(0.213)

Constant

− 3.129***

(0.627)

10.323***

(1.508)

4.213***

(0.552)

2.729***

(0.768)

0.749

(0.565)

2.571***

(0.832)

3.600***

(0.110)

Observations

300

93

49

44

53

42

19

R²

0.532

0.645

0.505

0.577

0.614

0.461

0.887

Adjusted R²

0.514

0.602

0.375

0.448

0.523

0.309

0.855

Residual SE

1.765

(df = 288)

2.606

(df = 82)

1.311

(df = 38)

1.152

(df = 33)

0.635

(df = 42)

0.407

(df = 32)

0.245

(df = 14)

F statistic

29.706***

(df = 11; 288)

14.924***

(df = 10; 82)

3.882***

(df = 10; 38)

4.495***

(df = 10; 33)

6.693***

(df = 10; 42)

3.035***

(df = 9; 32)

27.450***

(df = 4; 14)