\[ y_{i}=\beta_{1}+\beta_{2} x_{i 2}+\beta_{3} x_{i 3}+\varepsilon_{i}=x_{i}^{\prime} \beta+\varepsilon_{i} \] a. Explain how the ordinary least squares estimator for \( \beta \) is determined and derive an expression for \( b \). b. Which assumptions are needed to make \( b \) an unbiased estimator for \( \beta \) ? c. Explain how a confidence interval for \( \beta_{2} \) can be constructed. Which additional d. Explain how one can test the hypothesis that \( \beta_{3}=1 \).

In a normal distribution, a data value located 1.4 standard deviations below the mean has Standard Score: \( \mathrm{z}=-1.4 \) In a normal distribution, a data value located 2.3 standard deviations above the mean has Standard Score: \( \mathrm{z}=2.3 \) In a normal distribution, the mean has Standard Score: \( \mathrm{z}=\square \)

Consider the Standard Normal distribution. The mean is always \( \square \) and the standard deviation is always

In a normal distribution, a data value located 1.2 standard deviations below the mean has Standard Score: \( \mathrm{z}=\square \) In a normal distribution, a data value located 2.4 standard deviations above the mean has Standard Score: \( \mathrm{z}=\square \) In a normal distribution, the mean has Standard Score: \( \mathrm{z}=\square \)

Which of the following statements are TRUE about the Normal Distribution? Check all that apply. The graph of the Normal Distribution is bell-shaped, with tapering tails that never actually touch the horizontal axis. \( 50 \% \) of the data values lie at or above the mean. about \( 95 \% \) of all data values lie within 1 standard deviation of the mean. The mean, median and mode are all equal and occur at the center of the distribution. Data values are spread evenly around the mean. Data values farther from the mean are less common than data values closer to the mean.

Which of the followring statements are TRUE about the Hormal Distribution? Check all that apply. \( \square \) The distribution is symmetric with a single peak. \( \square \) about \( 95 \% \) of all data values lie within 1 standard deviation of the mean. \( \square \) The graph of the Hormal Distribution is bell-shaped, with tapering tails that never actually touch the horizontal axis. \( \square \) Data values farther from the mean are less common than data values closer to the mean. \( \square 50 \% \) of the data values lie at or above the mean. Data values are spread evenly around the mean. The mean, median and mode are all equal and occur at the center of the distribution.