Mary Noticed That Old Coins Are Smoother and More Worn $$\begin{array} { c c r l } r ^ { 2 } & 0.442 & n & 31 \\r & - 0.665 & k & 1 \\\text { or } & 0.050 & \text { Dep. Var. Weight (gm) }\end{array}$$

question 119

Essay

Mary noticed that old coins are smoother and more worn. She weighed 31 nickels and recorded their ages, and then performed a simple regression to estimate the model Weight = β₀ + β₁ Age, where weight is the weight of the coin in grams and Age is the age of the coin in years. Her results are shown below. Write a brief analysis of these results, using what you have learned in this chapter. Make a prediction of Weight when Age = 10 and also when Age = 20. What does this tell you? Is the intercept meaningful in this regression?
Regression Analysis
$$\begin{array} { c c r l } r ^ { 2 } & 0.442 & n & 31 \\r & - 0.665 & k & 1 \\\text { or } & 0.050 & \text { Dep. Var. Weight (gm) }\end{array}$$

ANOVA table
$\begin{array}{rcccrr}\hline \text { Source } & \text { SS } & \text { df } & M S & F & p \text {-value } \\\hline \text { Regression } & 0.0582 & 1 & 0.0582 & 22.99 & 4.48 \mathrm{E}-05 \\\text { Residual } & 0.0734 & 29 & 0.0025 & & \\\hline \text { Total } & 0.1316 & 30 & &\end{array}$


Regression output                                                 confidence interval
$\begin{array}{crrrrrr}\hline \text { variables } & \text { coefficients } & \text { std. emor } & f(d f=29) & \text { p-value } & 95 \% \text { lower } & 95 \% \text { upper } \\\hline \text { Intercept } & 5.0210 & 0.0137 & 367.740 & 9.33 \mathrm{E}-55 & 4.9931 & 5.0489 \\\text { Age (Yrs) } & -0.0040 & 0.0008 & -4.795 & 4.48 \mathrm{E}-05 & -0.0057 & -0.0023 \\\hline\end{array}$

Understand the legal consequences of anticompetitive behaviors such as price-fixing, market division, and predatory pricing.

Comprehend the role of the rule of reason and per se violations in antitrust law analysis.

Appreciate the global reach and limitations of U.S. antitrust laws in regulating international firms and agreements.

Grasp the significance of defining relevant market and monopoly power in antitrust cases.

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Definitions:

Tunicates

Marine invertebrates, also known as sea squirts, that are part of the subphylum Tunicata, characterized by a tough outer tunic and filter-feeding mode of nutrition.

Lancelets

Small marine animals belonging to the subphylum Cephalochordata, characterized by their fish-like shape and a notochord extending the length of their body.

Out-of-Africa Hypothesis

A theory suggesting that modern humans originated in Africa before dispersing to other parts of the world.

Homo Sapiens

The species name for modern humans, characterized by bipedalism and a large brain capacity relative to body size.