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Creates a baseline population by matching individuals in the trip set to individuals in the physical activity (PA) dataset

Usage

create_base_pop(raw_trip_set)

Arguments

raw_trip_set

data frame of raw trips taken, bus_driver, new motorcycle and truck trips have already been added

Value

the baseline population and the trip set which has been pruned

Details

The function performs the following steps:

  • adds age category to trip and physical activity datasets by calling assign_age_groups.R

  • To match people in trip data with people in the physical activity dataset:

    • create a baseline population by taking the unique participant ids together with age and gender information from the trip data (not including bus driver, truck, car driver and commercial motorcycle trips)

    • to assign non-occupational physical activity MMET values to this baseline population, the following steps are performed:

      • for each sex and age category, find the proportion of people with zero non-occupational MMET values and also find the list of people with non-zero MMET values

      • if BACKGROUND_PA_CONFIDENCE < 1 when calling the value of information script, i.e. when input values are sampled from distributions, a beta distribution is built from which the proportion of people with zero work and leisure MMET values is sampled using the known proportion as mean of this distribution

      • sample with replacement from a vector with 0 MMET values and the vector non-zero MMET values (from the people having non-zero work and leisure MMET values) using the proportion of people with zero work and leisure MMET values and assign those sampled MMET values to the baseline population

  • remove participants with trip or stage modes that are not in Vehicle inventory