Multiple Models

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Multiple Models

Often, a range of models involving time and group effects are desired at the beginning of an analysis to evaluate the importance of these effects on each of the basic parameters.  The Pre-defined Models option under the Run Menu generates a list of models based on the parameter constant across groups and time (.), the parameter varying across groups but constant with time (g), the parameter constant across groups but varying with time (t), and the parameter varying with both groups and time (g*t).  If only one group is involved in the analysis, then only the (.) and (t) models areprovided.  This list is generated for each of the parameters in the model.   Thus, for live recapture data with >1 group, a total of 16 models are provided to select for estimation: 4 models of phi times 4 models of p.  As another example, suppose a joint live recapture and dead recovery model with only one group is being analyzed.  Then, each of the 4 parameters would have the (.) and (t)  models, giving a total of 2 times 2 times 2 times 2 = 16 models.

You do not have to run every model in the list, selecting just the models you want to run to obtain numerical estimates.  Selection of one or more models from the list means that the program does not provide the same level of interaction.  For example, you will not be asked to accept the results of an estimation, but rather, the results will automatically be appended to the  results database.  This feature is to provide an easy way to add a large  number of models to the results database (e.g., during an overnight run) without constant attention.

When you have completed your selection, click on the OK button to proceed with estimation.  Otherwise, click on the Cancel button to return to the previous window without making any changes.