Exam 20: Time-Series Analytics and Forecasting

Coffee Imports The coffee imports (in millions of dollars)from a Latin American country for 10 years are shown below. ​ ​ -{Coffee Imports Narrative} Use the regression technique to calculate the linear trend line.

For which of the following values of the smoothing constant w will the smoothed series catch up most quickly whenever the original time series changes direction?

The mean absolute deviation averages the absolute differences between the actual values of the time series at time t and the forecast values at time:

The trend line = 0.75 + 0.005t was calculated from quarterly data for 2000-2004,where t = 1 for the first quarter of 2000.The trend value for the second quarter of the year 2005 is ____________________.

The time series component that reflects the irregular changes in a time series that are not caused by any other component,and tends to hide the existence of the other more predictable components,is called random variation.

We calculate the three-period moving average for a time series for all time periods except the first period.

Carpet Outlet A carpet outlet has been keeping daily sales records over the past four weeks as shown below. ​ ​ -{Carpet Outlet Narrative} Calculate the daily indexes based on the regression trend line in the previous question.

The way a seasonal index is computed involves which of the following steps?

One application of seasonal indexes is to remove the seasonal variation in a time series.The process is called deseasonalizing,and the result is called a seasonally adjusted time series.

The autoregressive model = 200 + 15yt− ₁ was developed from a time series.Forecast the next value of the time series if the last observation was 8.

The time series component that reflects a long-term,relatively smooth pattern or direction exhibited by a time series over a long time period (more than one year)is called:

Daily Hoagie Sales The table below shows the number of hoagies sold daily during a four-week period at Hoagie Haven in Sutton,West Virginia. ​ ​ -{Daily Hoagie Sales Narrative} Calculate the seasonal (daily)indexes,using the trend line developed in the previous question.

If a time series displays a gradual or no trend and no evidence of seasonal variation,____________________ can be effective as a forecasting method.

An estimated second-order autoregressive model for average mortgage rate is: .If the average mortgage rate in 2004 was 6.5 and in 2011 was 6.0,the forecast for 2013 is ____________________.

A trend is one of the four different components of a time series.It is a long-term,relatively smooth pattern or direction exhibited by a series,and its duration is more than one year.

Liquor Sales The number of cases of liquor sold by a liquor wholesaler in an 8-year period follows. ​ ​ -{Liquor Sales Narrative} A centered 3-year moving average is to be constructed for the liquor sales.The result of this process will lead to a total of ____________________ moving averages.

The time series component that reflects a long-term,relatively smooth pattern or direction exhibited by a time series over a long time period is called seasonal.

If the time series displays a gradual or no trend and no evidence of seasonal variation,exponential smoothing is not an effective as a forecasting method.

ebay Storefront Sales The sales figures (in $1000s)have been recorded in an ebay storefront as shown in the following table. ​ ​ -{ebay Storefront Sales Narrative} Calculate the percentage of trend for each time period.

Which of the following statements is true?