Table 3.
List of variables in the random forest model for predicting synthetic drug-related activity hot zones
| Variable name | Category | Description |
|---|---|---|
| GasStation | Built environment | Number of gas stations in each U.S. census block group |
| VacLot | Built environment | Number of vacant lots in each U.S. census block group |
| VacBldg | Built environment | Number of vacant buildings in each U.S. census block group |
| ParkingLot | Built environment | Number of parking lots in each U.S. census block group |
| AlleyDen | Built environment | Alley density |
| ParkArea | Built environment | Area of park propertied in each U.S. census block group |
| HighSch | Built environment | Number of high schools in each U.S. census block group |
| POccupyHouse | Built environment | % of house occupancy |
| POwner | Built environment | % of house ownership |
| PRenter | Built environment | % of house rent |
| AC_UNPR | Built environment | Total land area (not include park or conservation area) |
| D3b | Built environment | Street intersection density |
| D3bmm3 | Built environment | Auto- and pedestrian-oriented intersection (three legs) density |
| D1A | Built environment | Gross residential density |
| D1C5_Ret10 | Built environment | Gross retail employment density |
| D1D | Built environment | Gross activity density (employment and house units) |
| D2A_EPHHM | Built environment | Employment and household entropy |
| TotPop | Sociodemographic | Total population in each U.S. census block group |
| TotHH | Sociodemographic | Total households in each U.S. census block group |
| PMale | Sociodemographic | Percentage of male population |
| PFemale | Sociodemographic | Percentage of female |
| PWhite | Sociodemographic | % of population selecting race as white American alone |
| PBlack | Sociodemographic | % of population selecting race as black/African American alone |
| Pasian | Sociodemographic | % of population selecting race as Asian American alone |
| Phispanic | Sociodemographic | % of population selecting race as Hispanic/Latino American alone |
| PBachelorHigher | Sociodemographic | % of population with college level degree |
| MedianHHIncome | Sociodemographic | Median household income |
| PPovertyHouse | Sociodemographic | % of household in poverty status |
| PPovertyIndv | Sociodemographic | % of population in poverty status |
| PEmploy | Sociodemographic | % of full time and part time employees |
| Punemploy | Sociodemographic | % of unemployment |
| PFulltimeEmploy | Sociodemographic | % of full-time employment among all employment |
| PParttimeEmploy | Sociodemographic | % of part-time employment among all employment |
| P_WRKAGE | Sociodemographic | % of population that is working aged |
| PCT_AO0 | Sociodemographic | % of zero-car households |
| PCT_AO2P | Sociodemographic | % of two-plus-car households |
| R_HIWAGEWK | Sociodemographic | Number of high wage workers |
| R_PCTLOWWA | Sociodemographic | % low wage workers |
| E8_RET10 | Sociodemographic | Retail jobs |
| E8_OFF10 | Sociodemographic | Office jobs |
| HS_t_1 | Spatial and temporal lag variables | Time-lagged variable (whether this BG belonged to a hotspot at t-1 period) |
| nb_t_1 | Spatial and temporal lag variables | Spatiotemporally lagged variable (number of neighboring BGs belonged to a hotspot at t-1 period) |
| trend | Spatial and temporal lag variables | Trend variable (increase or decrease in the number of neighboring block groups that belonged to a hotspot at t-1 period) |