回归方程里，每一个自变量下面括号里的数字是什么意思，自变量的标准差？

问题如下：

Data were collected from a random sample of 220 home sales. Price is the dependent variable. The regressors (independent variables) are: BDR is number of bedrooms, Bath is number of bathrooms, HSize is size of house in square feet, LSize is lot size (in square feet), Age is age of house (in years), and Poor is a binary variable that is equal to one if the condition of the house is reported as "poor." The estimated regression, with included standard errors, is given by:

If a homeowner purchases 1,000 square feet from an adjacent lot (i.e., +1,000 to her lot size), what is the 99% confidence interval for the change in value to her house?

选项：

A.

+$76 to $324

B.

+$275 to $1,512

C.

+$763 to $3,236

D.

+1,255 to $4,871

解释：

The 99.0% confidence interval for the partial slope (partial effect) coefficient, LSize, is given by: 0.002 +/- 0.000480 * 2.58 = 0.000764 to 0.003236.

The effect of an 1,000 increase in lot size = +1,000 * (0.000764 to 0.003236) = +$764 to $3,236