(Requires Appendix)The Sample Average of the OLS Residuals Is

question 21

Multiple Choice

(Requires Appendix) The sample average of the OLS residuals is

• A)some positive number since OLS uses squares.
• B)zero.
• C)unobservable since the population regression function is unknown.
• D)dependent on whether the explanatory variable is mostly positive or negative.

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Definitions:

Through-beam Sensor

A type of photoelectric sensor where the emitter and receiver are positioned opposite each other, detecting objects when the beam is interrupted.

Sensing Range

The distance within which a sensor can detect the presence of an object or a signal.

NC Pushbutton

A Normally Closed pushbutton switch that makes contact (closes) when at rest and breaks the circuit when pressed.