Use the Data Given Below to Answer the Following Question(s)

question 18

Multiple Choice

Use the data given below to answer the following question(s) .
The table provided below gives the sales details of the number of android smart phones at an electronic retail store for the past 6 weeks. The time series appears to be relatively stable, without trend, seasonal, or cyclical effects. (Hint: Optimize α value in 0.1 increments) $$\begin{array} { | c | c | } \hline \text { Week } & \text { Units sold } \\\hline 1 & 88 \\\hline 2 & 44 \\\hline 3 & 54 \\\hline 4 & 65 \\\hline 5 & 72 \\\hline 6 & 85 \\\hline\end{array}$$
-Which of the following is the value of the root mean square error for the given data?

• A) 11.56
• B) 21.77
• C) 13.87
• D) 20.13

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Definitions:

Standard Deviation

A measure of the amount of variation or dispersion in a set of values, showing how spread out the data points are from the mean.

Chi-squared Distribution

A statistical distribution that is used to describe the distribution of a sum of squared random variables, often used in hypothesis testing.

Chi-squared Distribution

A statistical distribution that describes the distribution of the sum of the squares of a set of variables that follow a normal distribution, commonly used in hypothesis testing.

Positively Skewed

A distribution shape where the tail is longer on the right side, indicating that the mean and median are greater than the mode.