Which of the Following Is the Equation Used for Computing $\frac { \operatorname { cov } ( X , Y ) } { s _ { x } s _ { y } }$

question 7

Multiple Choice

Which of the following is the equation used for computing the sample correlation coefficient?

• A) r_xy = cov(X,Y)(sxsy)
• B) r_xy = \(\frac { \operatorname { cov } ( X , Y ) } { s _ { x } s _ { y } }\)
• C) r_xy = \(\frac { \left( x _ { i } - \bar { x } \right) } { s _ { x } s _ { y } }\)
• D) r_xy = \(\sqrt { \frac { \left( x _ { i } - \bar { x } \right) } { s _ { x } - s _ { y } } }\)

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Definitions:

Economies of Scale

The cost advantages that enterprises obtain due to their scale of operation, with cost per unit of output generally decreasing with increasing scale as fixed costs are spread out.

Average Variable Costs

represent the variable costs (costs that change with output level) per unit of output, calculated by dividing the total variable costs by the quantity of output produced.

Marginal Cost

The cost of producing one additional unit of a product, calculated by the change in total cost divided by the change in quantity.

Total Fixed Cost

The sum of all costs that remain constant regardless of the level of production or output within a business.