Table 4.
Structure and performance of the selected models.
| Province | Type of model | Value of parameters and/or their combinations | Prediction of model and number of years | Real events in these years | % of correct classifi-cations |
|---|---|---|---|---|---|
| Astrakhan | ExpMod 1A * | December—January T > −4.0 °C | Increase for 6 years | Increase in 6 years | 100% |
| December-January T ≤ −4.0 °C and May T ≥ 20.5 °C | Increase for 1 year | Increase in 1 year | 100% | ||
| December-January T ≤ −4.0 °C and May T < 20.5 °C | Decrease for 5 years | Decrease in 4 years, stability in 1 year ** | 80% | ||
| Total % of correct classifications for ExpMod 1A | 92% | ||||
| Astrakhan | ExpMod 2A * | WN_IN_PY *** < 3.0 and December T > −4.0 °C | Increase for 6 years | Increase in 6 years | 100% |
| WN_IN_PY < 3.0 and December T < −4.0 °C | Stability for 1 year | Stability in 1 year | 100% | ||
| WN_IN_PY > 3.0 and January T > −2.0 °C | Increase for 1 year | Increase in 1 year | 100% | ||
| WN_IN_PY > 3.0 and January T < −2.0 °C | Decrease for 4 years | Decrease in 4 years | 100% | ||
| Total % of correct classifications for ExpMod 2A | 100% | ||||
| Volgograd | ExpMod 1V | May—June T > 19.5 °C | Increase for 3 years | Increase for 3 years | 100% |
| May—June T ≤ 19.5 °C and September T > 16.5 °C | Stability for 5 year | Stability in 5 year | 100% | ||
| May—June T ≤ 19.5 °C and September T ≤ 16.5 °C | Decrease for 4 years | Decrease in 4 years | 100% | ||
| Total % of correct classifications for ExpMod 1V | 100% | ||||
| Volgograd | ProMod 1V | WN_IN_PY > 0.15 and June T > 21.0 °C | Increase for 3 years | Increase in 3 years | 100% |
| WN_IN_PY < 0.15 | Stability for 4 year | Stability in 4 year | 100% | ||
| WN_IN_PY > 0.15 and June T < 21.0 °C | Decrease for 5 years | Decrease in 4 years, stability in 1 year ** | 80% | ||
| Total % of correct classifications ProMod 1V | 92% | ||||
| Rostov | ExpMod 1R * | May T > 16.5 °C | Increase for 5 years | Increase in 5 years | 100% |
| May T < 16.5 °C and January T > −3.0 °C | Increase for 2 years | Increase in 1 years, stability in 1 year ** | 50% | ||
| May T < 16.5 °C and January T ≤ −3.0 °C | Decrease for 5 years | Decrease in 4 years, stability in 1 year ** | 80% | ||
| Total % of correct classifications ExpMod 1R | 83% | ||||
| Rostov | ExpMod 2R * | WN_IN_PY < 0.40 and May T > 16.5 °C | Increase for 5 years | Increase in 5 years | 100% |
| WN_IN_PY < 0.40 and May T < 16.5 °C and December—January T > −2.0 °C | Increase for 2 years | Increase in 1 years, stability in 1 year ** | 50% | ||
| WN_IN_PY < 0.40 and May T < 16.5 °C and December—January T < −2.0 °C | Decrease for 3 years | Decrease in 2 years, stability in 1 year ** | 67% | ||
| WN_IN_PY > 0.40 | Decrease for 2 years | Decrease in 2 years | 100% | ||
| Total % of correct classifications ExpMod 2R | 83% | ||||
| Astrakhan Volgograd Rostov | ExpMod 1AVR | May T ≥ 18.0 °C and WN_IN_PY ≤ 2.5 | Increase for 11 years | Increase in 11 years | 100% |
| May T ≥ 18.0 °C and WN_IN_PY > 3.0 and January T > −2.5 °C | Increase for 1 year | Increase in 1 year | 100% | ||
| May T ≥ 18.0 °C and WN_IN_PY > 3.0 and January T < −2.5 °C | Decrease for 2 years | Decrease in 2 years | 100% | ||
| May T < 18.0 °C and WN_IN_PY ≤ 0.3 and August-September T > 22 °C | Increase for 3 years | Increase in 3 years | 100% | ||
| May T < 18.0 °C and WN_IN_PY ≤ 0.3 and August-September T < 22 °C | Stability for 9 years | Stability in 7 years, increase in 1 year, decrease in 1 year | 78% | ||
| May T < 18.0 °C and WN_IN_PY > 0.3 | Decrease for 9 years | Decrease in 8 years, stability in 1 year | 89% | ||
| Total % of correct classifications ExpMod 1AVR | 92% | ||||
* This model was also the best ProMod, as it has been developed using only parameters obtained before the beginning of the “epidemic season” (July-October current year); ** Less frequent outcomes shown in italics are formally considered as “errors of prediction”; *** WN_IN_PY means “WND incidence in the previous year”, no. of cases per 100,000 population.