NEWS.md
A new model, mahlkow_wanner_2021, and bug fixes for caliendo_parro_2015 and chowdhry_hinz_kamin_wanner_2022. Results of multi-sector caliendo_parro_2015 runs without export subsidies are bit-identical to 26.09. Results of chowdhry_hinz_kamin_wanner_2022 runs change through its new numeraire (see below); on baselines whose trade balances sum to zero they change only within solver tolerance.
mahlkow_wanner_2021: carbon tax, climate club and border carbon adjustment. Extends caliendo_parro_2015 with a carbon tax that the members of a climate club (countries_climate_club) levy on the carbon content (carbon_intensity) of all goods used at home, a border carbon tariff on the carbon embodied in imports from non-members (scenario_carbon_tariff) and an export rebate on exports to non-members (scenario_export_rebate), both in the sectors cbam_sector. The tax is per unit of carbon, so the model needs initial price levels (price). It supports all instruments, trade-balance rules and settings of caliendo_parro_2015, one-sector models and the same numeraire (world value added). Without a carbon tax it reproduces caliendo_parro_2015. process_results() adds tax revenue, border carbon tariff revenue, export rebate costs, emissions and price levels, includes the tax revenue in income, and reports a tax-inclusive consumer price index.process_results() failed for caliendo_parro_2015 and the chowdhry_hinz_kamin_wanner_2022 solver failed in its expenditure and transfer updates. A new internal helper, slice_matrix(), keeps such slices as matrices. Behaviour change: country x sector results of one-sector runs (e.g. price_change) now keep their sector column.chowdhry_hinz_kamin_wanner_2022, process_results() now adds the solver’s coalition transfer to income_new, so income_change and welfare_change include it. Coalition members now show the common welfare change that the transfer rule sets. Runs without a coalition do not change.chowdhry_hinz_kamin_wanner_2022 solver now computes value_added_new from trade flows net of tariffs and export subsidies, as caliendo_parro_2015 does. This changes value_added_new and, under the fixed_country_share and fixed_global_share trade-balance rules, the equilibrium, whenever export subsidies differ from one.chowdhry_hinz_kamin_wanner_2022 solver no longer returns income_new, income_old or price_index_change, also when additional_output_variables requests them. The solver holds only work values for these (zeros, and ones for price_index_change). A requested income_new replaced the processed income, so income_change and welfare_change were 0 for every country. process_results() now always computes income_new and price_index_change from the solution.income_new from CP (#13). With additional_output_variables = "income_new", a caliendo_parro_2015 run solved, but process_results() failed with “object ‘country’ not found”: the solver’s income_new had a destination dimension, and it replaced the processed income. process_results() now always computes income_new itself (labour income, tariff revenue and export subsidy costs, less the trade balance). A requested income_new therefore no longer changes the processed results. The solver’s own income_new is its last inner iterate and differs from the processed one within solver tolerance. In the same way, for chowdhry_hinz_kamin_wanner_2022 a requested value_added_new replaced the processed one (wage change times baseline value added) by a value from before the final wage update. process_results() now ignores it, so a variable requested through additional_output_variables no longer changes any processed result. Behaviour change: the solver variables income, income_new, output and output_new, when requested, now have a country dimension instead of destination or origin. Runs that do not request them do not change.update_equilibrium() now warns when model_scenario sets a variable that the model does not read. Before, such a variable had no effect and no warning: for example, coalition_member_new for chowdhry_hinz_kamin_wanner_2022 gave zero coalition transfers. The warning has class kite_unknown_scenario_variable and the fields model and variables. It names the variable to set instead where one exists (coalition_member). Both solvers compute tariff_change and export_subsidy_change themselves, so these now warn and point to tariff_new and export_subsidy_new. Model functions outside the package are not checked. Results do not change.caliendo_parro_2015 rescales the wage change in every iteration so that world value added stays at its baseline level. chowdhry_hinz_kamin_wanner_2022 had no such rescale. Its excess-function wage update keeps the wage level only while the world trade balance sums to zero. Under fixed_country_share after a shock, and under any rule except zero on a baseline whose trade balances do not sum to zero, the wage level drifted without bound or collapsed, and the run did not converge. The solver now applies the rescale of caliendo_parro_2015 after its wage update, under every trade_balance_rule. On baselines whose trade balances sum to zero, results under fixed, fixed_global_share and zero change only within solver tolerance (in a comparison run with solver tolerance = 1e-10, wage changes moved by at most 5e-11 and welfare changes by at most 4e-10). fixed_country_share and unbalanced-baseline runs change materially: they now converge, and without a coalition they stay on the scale of caliendo_parro_2015. In these runs the trade-balance rule cannot hold for the world as a whole, so the two solvers stop at fixed points that differ slightly.update_equilibrium() still reported convergence = TRUE, but labour markets did not clear and the result depended on vfactor. This happens with trade_balance_rule = "fixed_country_share" after a shock, and on a baseline whose trade balances do not sum to zero under every rule except zero. update_equilibrium() now checks the world sum of trade_balance_new after the solve, with tolerance settings$tolerance_accounting (default 1e-6) times world value added, and also refuses solutions with non-positive value added. The default lets rounding residuals in data pass; the infeasible cases above typically leave residuals of 1e-4 of world value added or more. tolerance_accounting must be a single finite number >= 0. If the check fails, convergence is FALSE and a warning of class kite_world_trade_balance (fields model and accounting) explains why. The new results$info$accounting holds the details for every run. The check uses only the solver output, so it applies to every model in the package. Results do not change: outputs of all runs are bit-identical to before; only info changes.Public release. Merges release/26.05 into main.
License: GPL-3 in DESCRIPTION. Alternative or commercial licensing terms remain available on request from KITE@kielinstitut.de.trade_elasticity as the positive Fréchet parameter theta; legacy inverse and sign conventions are converted with a warning.update_equilibrium() and process_results() have been redesigned around an S3 result type. Existing 24.01 scripts will need a one-time migration.
| Surface | What changed | Migration |
|---|---|---|
update_equilibrium() return |
Plain list → S3-classed kite_result with a model-specific subclass and an attached info block (convergence, criterion, iterations, elapsed_seconds). |
Top-level element names (model, initial_conditions, model_scenario, output, settings) are preserved. Code accessing those by name keeps working. |
process_results() |
Plain function with internal if branches → S3 generic dispatching on the model class set by update_equilibrium(). |
User-facing call process_results(result) is unchanged. Custom downstream methods should adopt S3 (process_results.<class>). |
settings list |
New optional keys: vfactor (defaults to 0.1), convergence_method (defaults to "root_mean_square"), tolerance_expenditure, tolerance_output, require_inner_convergence (defaults to TRUE), max_inner_iterations (defaults to 5000). |
Existing scripts continue to work; pass vfactor or any other key explicitly only if you want to override the default. The old tolerance is still accepted as a fallback for both per-loop tolerances. |
cast_variable() default variable_order
|
The default index ordering has been simplified. | Pass variable_order = c(...) explicitly if you relied on the old default. |
| Initial conditions | The 24.01 helper used to iterate baseline wages/expenditures to model consistency. 26.05 expects pre-calibrated initial conditions (the package no longer ships an iteration helper). | Use initial-conditions data shipped with the model or built externally; contact KITE@kielinstitut.de for a calibrated baseline. |
array_sum() and array_sweep() are exported helpers for vector / sweep operations across named array margins, matching base::sweep() semantics.check_convergence() and format_time_diff() are exported diagnostic helpers.inst/examples/example.R is a shipped end-to-end tutorial. Locate it via system.file("examples", "example.R", package = "KITE").inst/CITATION provides two bibentry calls — the KITE Whitepaper as the canonical reference and a Manual entry for the package version itself. citation("KITE") returns both.inst/KITE.bib ships the same two entries in plain BibTeX for direct copy-paste.