Table 2.
Time series model analysis.
| Model | Number of predictive variables | Model fitting statistics | Ljung-Box Q (18) | Number of outliers | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Steady R2 | R2 | RMSE | MaxAPE | Normalized BIC | Statistic | DF | Sig. | |||
| b-FSH-Model_1 | 0 | 0.000 | 0.000 | 8.897 | 334.961 | 4.445 | 34.262 | 18.000 | 0.012* | 0.000 |
| b-LH-Model_2 | 0 | 0.000 | 0.000 | 5.366 | 481.939 | 3.434 | 43.588 | 18.000 | 0.001** | 0.000 |
| b-E2-Model_3 | 0 | 0.296 | 0.487 | 110.699 | 768.207 | 9.487 | 15.019 | 17.000 | 0.594 | 0.000 |
| b-P-Model_4 | 0 | 0.360 | 0.419 | 0.153 | 299.998 | -3.527 | 11.613 | 17.000 | 0.823 | 0.000 |
| b-T-Model_5 | 0 | 0.000 | 0.000 | 7.727 | 4701.794 | 4.163 | 15.287 | 18.000 | 0.642 | 0.000 |
| s-FSH-Model_1 | 0 | 0.283 | 0.283 | 5.514 | 336.360 | 3.636 | 22.183 | 16.000 | 0.137 | 0.000 |
| s-LH-Model_2 | 0 | 0.135 | 0.088 | 11.986 | 283.994 | 5.115 | 22.884 | 17.000 | 0.153 | 0.000 |
| s-E2-Model_3 | 0 | 0.000 | 0.000 | 106.415 | 219.877 | 9.409 | 13.679 | 18.000 | 0.750 | 0.000 |
| s-P-Model_4 | 0 | 0.144 | 0.144 | 13.333 | 2589.740 | 5.328 | 13.956 | 17.000 | 0.670 | 0.000 |
| s-T-Model_5 | 0 | 0.000 | 0.000 | 24.849 | 254.412 | 6.500 | 31.791 | 18.000 | 0.023* | 0.000 |
b-FSH, blood follicle stimulating hormone; b-LH, blood luteinizing hormone; b-P, blood progesterone; b-E2, blood estradiol; b-T, blood testosterone; s-FSH, seminal follicle stimulating hormone; s-LH, seminal luteinizing hormone; s-P, seminal progesterone; s-E2, seminal estradiol; s-T, seminal testosterone. R2, Square of correlation coefficient r; RMSE, Root Mean Square Error; MaxAPE, Maximum relative percentage error; BIC, BIC Bayesian Information Criterion; Ljung-Box Q(18), Ljung-Box Q-test for autocorrelation; DF, Degree of freedom; Sig., Significance. *: p<0.05; **: p<0.01.