inequality 0.1.0

• Initial release.

Inequality indices

• Gini coefficient with bootstrap or asymptotic (jackknife) confidence intervals via iq_gini(), following Davidson (2009).
• Extended S-Gini family with adjustable inequality aversion parameter via iq_sgini(), following Donaldson and Weymark (1980).
• Theil T (GE(1)), mean log deviation (GE(0)), and general GE(alpha) via iq_theil(), following Theil (1967) and Shorrocks (1980).
• Atkinson index with inequality aversion parameter via iq_atkinson().
• Kolm absolute inequality index via iq_kolm().
• Palma ratio (top 10% / bottom 40% income shares) via iq_palma().
• Hoover index (Robin Hood / Pietra index) via iq_hoover().
• Percentile ratios (P90/P10, P80/P20, custom) via iq_percentile_ratio().

Distribution and decomposition

• Lorenz curve with base graphics plot method via iq_lorenz().
• Between-within group decomposition for the generalised entropy family via iq_decompose(), following Bourguignon (1979).
• Income share tabulation (bottom 50%, middle 40%, top 10%, top 1%) via iq_shares().
• Concentration index for health inequality with optional Erreygers (2009) correction via iq_concentration().
• Wolfson bipolarisation index via iq_polarisation().

Poverty

• Foster-Greer-Thorbecke poverty measures (headcount, gap, severity), Sen index, and Watts index via iq_poverty().
• Growth incidence curve with plot method via iq_growth_incidence(), following Ravallion and Chen (2003).

Fiscal

• Kakwani progressivity index and Reynolds-Smolensky redistribution index via iq_kakwani().

Utilities

• Side-by-side comparison of all major indices via iq_compare().
• All functions accept optional survey weights.