Equation

Intercept

Per Capita Personal Income (t-statistic)

Per Capita Personal Income Squared (t-statistic)

Number of Counties (t-statistic)

Adjusted R²

Durbin-Watson

OLS

(1)

0.141708 (65.71)*

0.001374 (15.45)*

0.0956

0.0949

(2)

0.139969 (41.30)*

0.001585 (4.81)*

−0.00004 (−0.66)

0.0954

0.0954

(3)

0.112588 (33.02)*

0.001249 (4.10)*

0.000004 (0.80)

0.000468 (20.00)*

0.2319

0.1068

Random Effects

(1)

0.142310 (20.53)*

0.001345 (33.65)*

0.0956

0.0495

(2)

0.137128 (19.50)*

0.001986 (13.56)*

−0.000013 (−4.54)*

0.0946

0.0500

(3)

0.107370 (10.37)*

0.001972 (13.47)*

−0.000013 (−4.48)*

0.000487 (3.64)*

0.2272

0.0584