Identify a time dependent variable in your organization, business, or industry. Collect several measurements of this variable over time. Draw a scatter diagram of this variable versus time. What are...

Identify a time dependent variable in your organization, business, or industry. Collect several measurements of this variable over time. Draw a scatter diagram of this variable versus time. What are your observations?

Do you see any trend in the measurements? Explain.

Do you see any seasonal variation in the measurements? Explain.

Add a trend line to your scatter diagram, and determine the trend equation. Interpret the trend equation.

Purpose: To demonstrate the application of time series analysis in your organization, business, or industry.

Example: I work for an electric utility company. Over the years the demand for electricity has been growing constantly. The electricity demand measured in Megawatts is an example of a time dependent variable. When I plot the scatter diagram of electricity demand versus time, I see both an upward trend and seasonal variation. The upward trend is the result of growing demand over time. The electricity demand is high during the summer season, and is low during winter season. This pattern is repeated year after year.