Data for new regions

To apply this tool to data in a new region, you'll need the following data:

1. Catch data (mandatory) -- A data frame where each row is a single survey set (e.g., tow), with columns stating the latitude, longitude, year, area-swept (or other unit of survey effort), and catch (numbers or weight)

2. Survey grid (optional) -- A data frame representing a grid (preferably 2 nautical mile by 2 nautical mile), where each row represents a single grid cell. The data frame should have columns giving the latitude of the grid cell centroid, the longitude of the grid cell centroid, and the area of the grid cell that is within the survey domain of the sampling program (e.g., 0 for a cell that is entirely outside the area, 4 for a 2x2 nm cell that is entirely within the survey domain, and in between for a cell that is on the boundary of the domain). Because it is a grid, no two rows should have the exact same latitude and longitude for their centroids. If a survey grid is not available, the model will attempt to infer the sampling domain of the survey based on the location of samples. In this case, the inferred area might not exactly match the known sampling area, as used when calculation a design-based index. I therefore recommend that, if the model will be used for fisheries management, that collaborators work to provide a survey grid.