Initial Values for New Data Analyses

New data analyses are initiated in Program Mark by selecting the File, New options. You are asked to enter the Data Type, the number of Encounter Occasions, Number of Groups, Number of Individual Covariates, and the Number of Strata (if the data type is multi-strata). In general, you should specify the data type first, so that other options that depend on the data type will be initialized properly (particularly the number of time intervals).

You must specify the Encounter Histories File where the actual encounter history data will be provided, the number of animals in each group that had this encounter history, along with the Individual Covariates if your data includes them. More information is provided in Encounter Histories Format. To browse for the file, you can click on the Encounter Histories File button, or double click the edit box where the file name can be entered.

You may also need to specify the length of the Time Intervals. Once you have specified the number of encounter occasions, you can click on the Set Time Intervals button. Time Intervals are required for any of the Robust Design models, but are not specifed for the Closed Captures or Closed Captures Huggins Est. models. The number of time intervals to set depends on the data type. Data types with dead recoveries (i.e., the LDLDLDLD encounter history format) have the number of time intervals equal to the number of encounter occasions, whereas data types with only live encounters have one less time interval than the number of encounter occasions.

Once you have specified the number of groups, you can give each group a meaningful label to help interpretation during later analyses.

If the number of individual covariates is >0, you give them names by clicking on the Set Individual Covariates button. For the data type Closed Captures, no individual covariates are allowed.

If the number of strata is >0, you must specify the Strata Label and the Strata Name for each strata.

After you complete these entries and verify that they are correct, click on the OK button to proceed with parameter estimation.

There are no fixed upper limits on the numbers of groups, strata, or occasions. Rather, memory limitations of the computer doing the analysis set the upper limit of the size of problem that can be handled.