Closed christopherkenny closed 1 month ago
CoryMcCartan
commented
3 months ago The link to 2010 guidelines is broken. Let's cite the statute directly: https://law.justia.com/codes/hawaii/2011/division1/title3/chapter25/25-2/
In 2011 the guideline was to use tracts
christopherkenny
commented
1 month ago Per Hawaii Revised Statutes 25-2(b)(1)-(4) and (6), as in force for the 2010 cycle, districts must:
1. not unduly favor any person or party;
2. be contiguous, except when encompassing more than one island;
3. be compact;
4. where possible, follow geographical and recognized features and coincide with tract boundaries;
6. where practicable, avoid mixing regions with different socioeconomic interests.
We enforce a maximum population deviation of 0.5%. We use Census tracts in line with 25-2(b)(4). In absence of regional knowledge about features and socioeconomic interests, we use municipalities to attempt to enforce 25-2(b)(4) and (6).
Data for Hawaii comes from the ALARM Project's 2010 Redistricting Data Files.
Islands are manually connected in the adjacency graph, but this has no bearing on the simulation.
We sample 5,000 districting plans for Hawaii over 2 independent runs of the SMC algorithm. We use partial SMC to draw one district in the contiguous portion of Honolulu County and assign the remainder to district 2.
SMC: 5,000 sampled plans of 2 districts on 351 units
`adapt_k_thresh`=0.99 • `seq_alpha`=0.5
`pop_temper`=0
Plan diversity 80% range: 0.093 to 0.674
✖ WARNING: Low plan diversity
R-hat values for summary statistics:
pop_overlap total_vap plan_dev comp_edge comp_polsby pop_white pop_two pop_black
1.000 1.000 1.000 1.000 1.000 1.000 1.000 1.000
pop_hisp pop_aian pop_other pop_nhpi pop_asian vap_two vap_other vap_nhpi
1.000 1.000 1.000 1.000 1.000 1.000 1.000 1.000
vap_asian vap_hisp vap_black vap_white vap_aian pre_20_rep_tru pre_20_dem_bid pre_16_dem_cli
1.000 1.000 1.000 1.000 1.000 1.000 1.000 1.000
gov_18_rep_tup uss_16_dem_sch uss_16_rep_car gov_18_dem_ige uss_18_rep_cur pre_16_rep_tru uss_18_dem_hir arv_20
1.000 1.000 1.000 1.000 1.000 1.000 1.000 1.000
adv_16 adv_18 arv_18 adv_20 arv_16 muni_splits ndv nrv
1.000 1.000 1.001 1.000 1.000 1.000 1.000 1.001
ndshare e_dvs egap
1.000 1.000 1.001
Sampling diagnostics for SMC run 1 of 2 (2,500 samples)
Eff. samples (%) Acc. rate Log wgt. sd Max. unique Est. k
Split 1 2,451 (98.1%) 12.3% 0.29 1,591 (101%) 5
Resample 2,322 (92.9%) NA% 0.29 2,222 (141%) NA
Sampling diagnostics for SMC run 2 of 2 (2,500 samples)
Eff. samples (%) Acc. rate Log wgt. sd Max. unique Est. k
Split 1 2,451 (98.0%) 10.3% 0.29 1,567 ( 99%) 6
Resample 2,322 (92.9%) NA% 0.29 2,194 (139%) NA
• Watch out for low effective samples, very low acceptance rates (less than 1%), large std. devs. of the log weights (more than 3
or so), and low numbers of unique plans. R-hat values for summary statistics should be between 1 and 1.05.
• Low diversity: Check for potential bottlenecks. Increase the number of samples. Examine the diversity plot with
`hist(plans_diversity(plans), breaks=24)`. Consider weakening or removing constraints, or increasing the population tolerance. If
the acceptance rate drops quickly in the final splits, try increasing `pop_temper` by 0.01.
Redistricting requirements
Per Hawaii Revised Statutes 25-2(b)(1)-(4) and (6), as in force for the 2010 cycle, districts must:
1. not unduly favor any person or party;
2. be contiguous, except when encompassing more than one island;
3. be compact;
4. where possible, follow geographical and recognized features and coincide with tract boundaries;
6. where practicable, avoid mixing regions with different socioeconomic interests.
Algorithmic Constraints
We enforce a maximum population deviation of 0.5%. We use Census tracts in line with 25-2(b)(4). In absence of regional knowledge about features and socioeconomic interests, we use municipalities to attempt to enforce 25-2(b)(4) and (6).
Data Sources
Data for Hawaii comes from the ALARM Project's 2010 Redistricting Data Files.
Pre-processing Notes
Islands are manually connected in the adjacency graph, but this has no bearing on the simulation.
Simulation Notes
We sample 5,000 districting plans for Hawaii over 2 independent runs of the SMC algorithm. We use partial SMC to draw one district in the contiguous portion of Honolulu County and assign the remainder to district 2.
Validation
Checklist
TODOlines from the template code have been removedenforce_style()to format my coderedist_mapandredist_plansobjects, and summary statistics) have been edited@CoryMcCartan
Additional notes