| user_name | Erik Valinger |
| user_organisation | Swedish University of Agricultural Sciences Faculty of Forestry Department of Silviculture S-901 83 Umea Sweden |
| date | 21th May 1997 |
| model_name | Integrated model |
| description | Describes probability of snow and wind damage at sites using tree,
stand, and site characteristics from the thickest sample tree at each sample plot, and measured stand and site data from the same plot. |
| software | Developed in SAS 6.10 but Excel 7.0 will do |
| operating_system | PC Windows 95 |
| isumm | There are six input variables in model. The risk of damage is modeled using the characteristics height, volume ha-1, longitude, latitude, altitude, and crown length. Valid only for Norway spruce in mid Sweden. |
| Ispecfile | Similar to that for earlier Umea models |
| iexpspecfile | n/a |
| ivar1 | Height (h) |
| ifile1 | ? |
| idescr1 | m |
| isensitiv1 | Sensitive |
| isensdescr1 | Logistic procedure |
| ivar2 | Volume ha-1 (vha) |
| ifile2 | ? |
| idescr2 | 0.1 m3 ha-1 |
| isensitiv2 | Sensitive |
| isensdescr2 | Logistic procedure |
| ivar3 | Longitude (long) |
| ifile3 | ? |
| idescr3 | degrees |
| isensitiv3 | Sensitive |
| isensdescr3 | Logistic procedure |
| ivar4 | Latitude (lat) |
| ifile4 | ? |
| idescr4 | degrees |
| isensitiv4 | Sensitive |
| isensdescr4 | Logistic procedure |
| ivar5 | Altitude (alt) |
| ifile5 | m |
| isensitiv5 | sensitive> |
| isensdescr5 | Logistic procedure |
| ivar6 | Crown length (crl) |
| ifile6 | ? |
| idescr6 | m |
| isensitiv6 | Sensitive |
| csumm | height, h -0.1693 volume ha-1, vha 0.00411 longitude, long 0.2319 latitude, lat -1.3365 altitude, alt 0.00957 crown length, crl 0.1494 |
| Model | miprob=1-(1/(1+exp(71.8221-(0.1693*h)+(0.00411*vha) +(0.2319*long)-(1.3365*lat)+(0.00957*alt)+(0.1494*crl)))) (then multiply by 100 to get the result in percent) |
| cspecfile | None |
| cexpspec | mgran |
| ospecfile | ? |
| oexpspecfile | See above |
| ovar1 | miprob |
| ofile1 | ? |
| odescr1<?td> | Site probability of snow and wind damage |
| stat_meth | Logistic procedure for probability of damage from snow and wind at a site using tree, stand, and site characteristics when dominating species is Norway spruce Chi-square for covariates 869.469 with 6 DF (p=0.0001) Pr > Chi-square Intercept 0.0001 h 0.0001 vha 0.0001 long 0.0001 lat 0.0001 alt 0.0001 crl 0.0001 |
| mech_meth | n/a |
| log_meth | Logistic model Model miprob=1-(1/(1+exp(71.8221-(0.1693*h)+(0.00411*vha)+(0.2319*long) -(1.3365*lat)+(0.00957*alt)+(0.1494*crl)))) (then the result is multiplied by 100 to get it in percent) |
| scope | Model developed from a sample of data from mid Sweden (579 sample plots) 6.1% of the plots had one or more damaged sample trees, damage=1. Model have been proven to predict damage well by cross-validation |
| other | ? |
| copyright | Swedish University of Agricultural Sciences Faculty of Forestry Department of Silviculture |
| contact | Associate Professor Erik Valinger |