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Can someone explain why the 0.23 (Beta hat) turns negative?

15) You have collected data for the 50 U.S. states and estimated the following relationship between the change in the unemployment rate from the previous year ( $Δur)$ and the growth rate of the respective state real GDP $(g_{y})$. The results are as follows $Δur=2.81−0.23×g_{y},R2=0.36,SER=0.78(0.12)(0.04) $ Assuming that the estimator has a normal distribution, the $95%$ confidence interval for the slope is approximately the interval A) $[−0.31,0.15]$ B) $[2.57,3.05]$ C) $[−0.33,−0.13]$ D) $[−0.31,−0.15]$ Answer: D
The estimated value of the coefficient $β$ is 0.23 , with a standard error of 0.04 . Using the standard normal approximation, the $95%$ confidence interval for $β$ is required to be calculated. In the standard normal probability distribution table, the $z$-value corresponding to $0.4750(=0.95/2)$ is 1.96 ; therefore, the $95%$ confidence interval for $β$ can be calculated as follows: $95%confidence interval =β ±1.96(standard error ofβ )=0.23±1.96(0.04)=−0.23±0.08=−0.23−0.08and−0.23+0.08=−0.31and−0.15 $ Therefore, the $95%$ confidence interval for $β$ is from -0.31 and -0.15 ; is correct.