Summary Statistics for County-Level Variables Applied to Farm-Level Observations by Organic Status
| Total Sample | Conventional | Organic | |||||
|---|---|---|---|---|---|---|---|
| Mean | St. Dev. | Mean | St. Dev. | Mean | St. Dev. | ||
| Organic farms in county | 4.52 | 9.38 | 4.39 | 9.03 | 14.55 | 21.34 | *** |
| Proportion irrigated | 0.14 | 0.28 | 0.14 | 0.27 | 0.34 | 0.40 | *** |
| Soil productivity index (0-1) | 0.55 | 0.21 | 0.55 | 0.21 | 0.42 | 0.22 | *** |
| Household income ($/1,000) | 37.53 | 7.33 | 37.50 | 7.30 | 39.51 | 9.22 | ** |
| Urban-rural index (1-9) | 5.06 | 2.49 | 5.07 | 2.48 | 4.27 | 2.49 | *** |
| N | 37,535 | 36,484 | 1,051 | ||||
Note: Significance tests are conducted using Stata svy postestimation, which allows weighting (see www.stata.com/manuals13/rttest.pdf for details). All variables are from the USDA NASS Census of Agriculture, except the county soil productivity index, which is from the USDA NRCS Soil Survey Geographic Database (SSURGO). The urban-rural index takes on values of one through nine, where nine is the most rural. The number of organic farms per county was estimated in 2002 and household income in 1999 using census data.
* p < 0.1; ** p < 0.05; *** p < 0.01 (from t-tests of organic versus conventional means).