Economist
an Economist Is in the Process of Developing a Model

question 65

Short Answer

Economist
An economist is in the process of developing a model to predict the price of gold.She believes that the two most important variables are the price of a barrel of oil (x₁)and the interest rate (x₂).She proposes the first-order model with interaction $$y = \beta _ { 0 } + \beta _ { 1 } x _ { 1 } + \beta _ { 2 } x _ { 2 } + \beta _ { 3 } x _ { 1 } x _ { 2 } + \epsilon$$ A random sample of 20 daily observations was taken.The computer output is shown below. The regression equation is:
$$y = 115.6 + 22.3 x _ { 1 } + 14.7 x _ { 2 } - 1.36 x _ { 1 } x _ { 2 }$$
$\begin{array}{|l|ccc|}\hline \text { Predictor } & \text { Coef } & \text { SE Coef } & \text { T } \\\hline \text { Constant } & 115.6 & 78.1 & 1.480 \\x_{1} & 22.3 & 7.1 & 3.141 \\x_{2} & 14.7 & 6.3 & 2.333 \\x_{1} x_{2} & -1.36 & 0.52 & -2.615 \\\hline\end{array}$

$$\mathrm { S } = 20.9 \quad \mathrm { R } - \mathrm { Sq } = 55.4 \%$$
ANAL YSIS OF VARIANCE
$\begin{array}{|l|llll|}\hline \text { Source of Variation } & \text { DF } & \text { SS } & \text { MS } & \text { F } \\\hline \text { Regression } & 3 & 8661 & 2887.0 & 6.626 \\\text { Error } & 16 & 6971 & 435.7 & \\\hline \text { Total } & 19 & 15632 & & \\\hline\end{array}$

-Is there sufficient evidence at the 1% significance level to conclude that the interaction term should be retained?
Test statistic = ____________________ = ____________________
Critical Value = ____________________
Conclusion: _______________________
Interpretation: __________________________________________________

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Definitions:

Term Structure

The relationship between interest rates (or yields) and different terms (or maturities) for debt securities.

Liquidity Premium

The additional return that investors require for holding securities with low liquidity, compensating them for the higher risk associated with difficulty in selling the asset quickly at its fair market value.

Term Structure

The relationship between interest rates or yields of different debt instruments, usually depicted by a yield curve showing various maturities.

Real Rate of Interest

The yield a investor foresees receiving, once inflation adjustments are made.