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Create Transition Rates Table

Source: R/trans_rates_t.R
trans_rates_t.Rd

Creates a trans_rates_t table that stores transition rates (probabilities) for each transition type in each time period. Historical rates are calculated from observed transitions, and future rates are extrapolated using linear regression.

Usage

as_trans_rates_t(x)

create_obs_trans_rates_t(trans_v, trans_meta)

create_extr_trans_rates_t(obs_rates, periods)

# S3 method for class 'trans_rates_t'
print(x, nrow = 10, ...)

Arguments

x

A list or data.frame coercible to a data.table

trans_v

A transitions view table with columns: id_period, id_lulc_anterior, id_lulc_posterior, id_coord

trans_meta

A trans_meta_t table with transition metadata including id_trans, id_lulc_anterior, and id_lulc_posterior

obs_rates

A trans_rates_t table with observed historical rates

periods

A periods_t table defining the time periods

nrow

see data.table::print.data.table

...

passed to data.table::print.data.table

Value

A data.table of class "trans_rates_t" with columns:

  • id_period: Foreign key to periods_t

  • id_trans: Foreign key to trans_meta_t

  • rate: Transition rate (0 to 1)

Methods (by generic)

  • print(trans_rates_t): Print a trans_rates_t object, passing params to data.table print

Functions

  • create_obs_trans_rates_t(): Calculate observed transition rates from historical data. For each period and transition type, calculates the rate as the proportion of id_lulc_anterior cells that transitioned to id_lulc_posterior.

  • create_extr_trans_rates_t(): Extrapolate future transition rates using linear regression. For each transition type (id_trans), fits a linear model of rate vs period number and extrapolates to future periods. Negative predicted rates are set to 0.