The Last Four Weekly Values of Sales Were 80, 100

question 140

Essay

The last four weekly values of sales were 80, 100, 105, and 90 units. The last four forecasts (for the same four weeks) were 60, 80, 95, and 75 units. Calculate MAD, MSE, and MAPE for these four weeks.
$$\begin{array} { | c | c | c | c | c | } \hline \text { Sales } & \text { Forecast } & \text { Error } & \text { Error squared } & \text { Pct. error } \\\hline 80 & 60 & 20 & 400 & .25 \\\hline 100 & 80 & 20 & 400 & .20 \\\hline 105 & 95 & 10 & 100 & .095 \\\hline 90 & 75 & 15 & 225 & .167 \\\hline\end{array}$$

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Definitions:

Psychodynamic Theory

A psychological perspective that emphasizes the influence of the unconscious mind and childhood experiences on behavior and personality.

Evolutionary Theory

A scientific explanation for the diversity of life on Earth, proposing that species change over time through processes like natural selection and genetic mutation.

Masculinity and Femininity

Socially constructed roles, behaviors, expressions, and identities associated with being male or female, varying across different cultures and times.

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Determined by the chromosomes an individual inherits, typically XX for females and XY for males, influencing primary and secondary sex characteristics.