island_market_access(): distance-decayed market access,
MA_i = sum_j m_j * d_ij^-theta, the reduced-form measure used in economic
geography and in the remote-sensing literature on rural connectivity. Mass is
always user-supplied, because population and output are time-varying and the
reference year is the analyst's to document; the package supplies only the
geometry. Supports separate origins and destinations via to, an explicit
own-mass term via self, and any positive decay elasticity. Base R, no new
dependencies.islands dataset gains five coordinate columns (WGS84 decimal degrees): latitude/longitude (a representative point on each territory's main landmass) and capital/capital_latitude/capital_longitude (the capital city). Sourced from Natural Earth with a hand-curated supplement for the BES islands, French overseas departments, and other small territories; see the upstream island-research-reference-data for provenance.island_coords() returns coordinates for a vector of names or ISO codes, with which = "point" (default) or which = "capital".island_distance() gives great-circle (haversine) distances between islands: a full symmetric matrix among one set, or element-wise/recycled distances between two. Supports which (point or capital) and unit (km, mi, nmi). Base R, no new dependencies.islands. Its ISO 3166-1 alpha-2 code is the literal string "NA", which the data-build step previously treated as a missing value. The dataset now has 251 rows (was 250).Resubmission addressing CRAN reviewer feedback (Uwe Ligges).
License field simplified to CC BY 4.0; the + file LICENSE suffix and the accompanying boilerplate LICENSE file have been removed (the file was not used to specify additional restrictions on CC BY 4.0).Initial CRAN release.
islands reference dataset: 250 countries and territories with classifications for SIDS, SNIJ, World Bank region and income group, political association, and the four small-island defining criteria.is_sids(), is_snij(), is_small_island() accept country names, ISO codes, or the hyphenated BES sub-codes (BQ-BO, BQ-SE, BQ-SA).island_lookup() and add_island_cols() for tidy joining onto research data.small_islands() shorthand for filtered subsets.aruba() — A.R.U.B.A. (Annotated Reference for Under-coded Border Areas): a convenience wrapper around island_lookup() with Aruba as the default. A homage to Edward Cheung's A.R.U.B.A. (ASCS/NCS Relay Unit Breaker Assembly) on the Hubble Space Telescope.github.com/University-of-Aruba/island-research-reference-data under CC BY 4.0.