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问题如下：

Doug Abitbol is a portfolio manager for Polyi Investments, a hedge fund that trades in the United States. Abitbol manages the hedge fund with the help of Robert Olabudo, a junior portfolio manager.

Abitbol looks at economists’ inflation forecasts and would like to examine the relationship between the US Consumer Price Index (US CPI) consensus forecast and the actual US CPI using regression analysis. Olabudo estimates regression coefficients to test whether the consensus forecast is unbiased. If the consensus forecasts are unbiased, the intercept should be 0.0 and the slope will be equal to 1.0. Regression results are presented in Exhibit 1. Additionally, Olabudo calculates the 95 percent prediction interval of the actual CPI using a US CPI consensus forecast of 2.8.

Finally, Abitbol and Olabudo discuss the forecast and forecast interval:

■ Observation 1. For a given confidence level, the forecast interval is the same no matter the US CPI consensus forecast.

■ Observation 2. A larger standard error of the estimate will result in a wider confidence interval.

Based on Exhibit 1, Olabudo should:

选项：

conclude that the inflation predictions are unbiased.

reject the null hypothesis that the slope coefficient equals one.

reject the null hypothesis that the intercept coefficient equals zero.

解释：

A is correct. We fail to reject the null hypothesis of a slope equal to one, and we

fail to reject the null hypothesis of an intercept equal to zero. The test of the slope equal to 1.0 is