shellgame 0.1.0

Initial release

• audit_transformation() — main function to audit a full ZCTA → ZIP → County transformation pipeline and quantify perturbation.
• transform_zcta_to_zip() — performs the first hop (ZCTA → ZIP) using equal-weight allocation across associated ZIPs.
• transform_zip_to_county() — performs the second hop (ZIP → County) using HUD TOT_RATIO allocation.
• run_full_transformation() — convenience wrapper executing both hops in sequence.
• prep_zip_zcta() — standardizes raw ZIP-ZCTA crosswalk files for use in audits.
• prep_hud_crosswalk() — standardizes raw HUD ZIP-County crosswalk files.
• get_zcta_baseline() — fetches ACS 5-year estimates at ZCTA level via the Census API (requires tidycensus and a Census API key).
• extract_perturbed_population() — extracts the redistribution of population across receiving counties produced by the transformation.
• plot_transformation_perturbation() — bar chart of baseline vs recovered values with perturbation magnitude in subtitle.
• create_audit_report() — generates all visualizations for an audit.
• S3 print and summary methods for shellgame_audit objects.
• Vignettes: Hennepin County worked example, data preparation guide, conceptual framework.