Calculate Monthly Trip Statistics by District

Calculates monthly fishing activity statistics by district based on GPS-tracked boats. These are estimates from a sample of the total fleet and can be used to extrapolate fleet-wide fishing activity when combined with boat registry data.

Usage

calculate_monthly_trip_stats(trips_data)

Arguments

trips_data

A data frame containing trip information with columns:

• district: District name

• date_month: Month as date (first day of month)

• duration_hrs: Trip duration in hours

• boat: Unique boat identifier

Value

A data frame with monthly statistics by district containing:

• district: District name

• date_month: Month as date

• sample_total_trips: Total trips recorded from tracked boats

• sample_boats_tracked: Number of unique boats tracked

• avg_trip_duration_hrs: Average trip duration in hours

• avg_trips_per_boat_per_month: Average trips per boat (for scaling to fleet)

Details

The function processes trip data to generate monthly summaries including:

• Number of trips recorded from GPS-tracked boats

• Number of unique boats tracked per month

• Average trip duration in hours

• Average trips per boat per month (key metric for fleet scaling)

These metrics are particularly useful for estimating total fishing effort when GPS trackers are only installed on a subset of the fishing fleet.

See also

• estimate_fleet_activity() for scaling to total fleet

• calculate_district_totals() for catch and revenue estimates

Examples

if (FALSE) { # \dontrun{
# Calculate monthly statistics
monthly_stats <- calculate_monthly_trip_stats(trips_stats)

# View results
print(monthly_stats)
} # }