Table 4.
Regression results on the differences in aggregate shelf space of foods between African-American and mixed racial census tracts, New Orleans, LA, 2004-2005
| Food Shelf Space a | β b | SE | p-value | Mean difference c |
|---|---|---|---|---|
| Fruits | ||||
| Fresh | -1.34 | 0.61 | 0.03 | -19.7 |
| Canned | -0.09 | 0.35 | 0.79 | -1.1 |
| Frozen | -0.38 | 0.14 | 0.01 | -1.0 |
| Total | -1.17 | 0.65 | 0.08 | -22.4 |
| Vegetables | ||||
| Fresh | -1.47 | 0.67 | 0.03 | -27.3 |
| Canned | -0.10 | 0.54 | 0.85 | -1.8 |
| Frozen | -1.23 | 0.38 | 0.00 | -12.4 |
| Total | -1.54 | 0.89 | 0.09 | -42.3 |
| Energy-dense Snacks | ||||
| Salty Snacks | -0.29 | 1.10 | 0.79 | -12.1 |
| Cookies/Crackers/Pastries | -0.84 | 1.13 | 0.46 | -33.5 |
| Candy | -0.25 | 1.00 | 0.80 | -9.4 |
| Carbonated Beverages | 0.04 | 1.31 | 0.98 | 1.6 |
Each row represents a separate OLS square root transformed model in which the dependent variable is the amount of shelf space of a given food. Reference category is mixed racial tracts, i.e. less than 80% African-American residents. All models are adjusted for tract population density.
Beta-coefficients from the regression models are not readily interpretable since the dependent variables were square root transformed. A negative sign on the coefficient indicates a lower amount of aggregate shelf space for African-American tracts.
Mean difference in aggregate shelf space (meters) of specific foods between African-American and mixed racial tracts. Differences are calculated after back-transforming raw regression results to the original units, i.e. meters of shelf space. A mean tract population density of 3,820 pop/km2 was used in these calculations.