SCENARIO 16-12
a Local Store Developed a Multiplicative Time-Series Model $$\log _ { 10 } \hat { Y } = 6.102 + 0.012 X - 0.129 Q _ { 1 } - 0.054 Q _ { 2 } + 0.098 Q _ { 3 }$$

question 90

Short Answer

SCENARIO 16-12
A local store developed a multiplicative time-series model to forecast its revenues in future
quarters, using quarterly data on its revenues during the 5-year period from 2009 to 2013. The
following is the resulting regression equation: $$\log _ { 10 } \hat { Y } = 6.102 + 0.012 X - 0.129 Q _ { 1 } - 0.054 Q _ { 2 } + 0.098 Q _ { 3 }$$
where $\hat { Y }$ is the estimated number of contracts in a quarter
$X$ is the coded quarterly value with $X = 0$ in the first quarter of 2008 .
$Q _ { 1 }$ is a dummy variable equal to 1 in the first quarter of a year and 0 otherwise.
$Q _ { 2 }$ is a dummy variable equal to 1 in the second quarter of a year and 0 otherwise.
$Q _ { 3 }$ is a dummy variable equal to 1 in the third quarter of a year and 0 otherwise.
-Referring to Scenario 16-12, to obtain a fitted value for the fourth quarter of 2010 using the model, which of the following sets of values should be used in the regression equation? a) $X = 7 , Q _ { 1 } = 0 , Q _ { 2 } = 0 , Q _ { 3 } = 0$
b) $X = 7 , Q _ { 1 } = 1 , Q _ { 2 } = 0 , Q _ { 3 } = 0$
c) $X = 8 , Q _ { 1 } = 0 , Q _ { 2 } = 0 , Q _ { 3 } = 0$
d) $X = 8 , Q _ { 1 } = 1 , Q _ { 2 } = 0 , Q _ { 3 } = 0$

Understand how statistical design principles (control, randomization, blinding) contribute to the reliability of experimental results.

Understand the definition and identify different components of a time series (trend, cyclical, seasonal, random).

Distinguish between the four main components of a time series based on their characteristics and effects.

Know how to compute moving averages and understand their purpose in time series analysis.

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The quality of being easily understandable or free from ambiguity.

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A visual depth cue that results from the eyes' slightly different views of the world, allowing for depth perception.

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increasing velocity or speed, often in the context of physical movement, actions, or processes.

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A decrease in the speed at which physical movements or processes are conducted.