Compute the Variance and Standard Deviation of a Discrete Random $x$

question 104

Multiple Choice

Compute the Variance and Standard Deviation of a Discrete Random Variable
-In a sandwich shop, the following probability distribution was obtained. The random variable $x$ represents the number of condiments used for a hamburger. Find the mean and standard deviation for the random variable x.
$\begin{array}{c|c}x & P(x) \\\hline 0 & 0.30 \\1 & 0.40 \\2 & 0.20 \\3 & 0.06 \\4 & 0.04\end{array}$

• A) mean: \(1.14\); standard deviation: \(1.04\)
• B) mean: \(1.54\); standard deviation: \(1.30\)
• C) mean: \(1.30\); standard deviation: \(2.38\)
• D) mean: \(1.30\); standard deviation: \(1.54\)

Identify appropriate forecasting models based on characteristics of the time series such as trend and seasonality.

Calculate mean square error (MSE) for model accuracy assessment.

Calculate mean absolute percentage error (MAPE) for forecasting accuracy.

Understand the application of the double moving average model.

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Definitions:

Virtual Reality Exposure Therapy

A form of psychotherapy that uses virtual reality technology to expose patients to the situations or objects they fear, in a controlled and safe environment.

Posttraumatic Stress Disorder

A mental health condition triggered by experiencing or witnessing a terrifying event, characterized by flashbacks, nightmares, and severe anxiety.

Psychosis

A mental health condition characterized by a loss of connection with reality, manifesting through delusions, hallucinations, and disordered thinking.

Somatization Disorder

A psychological disorder characterized by the presence of physical symptoms that have no identifiable physical cause, often linked to emotional distress.