Exam 20: Time-Series Analytics and Forecasting

Microprocessors Annual production (in millions)of computer microprocessors in a large electronics company was recorded as shown below ​ ​ -{Microprocessors Narrative} Calculate the percentage of trend for each time period.

The time series component that reflects a wavelike pattern describing a long-term trend that is generally apparent over a number of years is called:

The regression trend line for annual energy consumption for 2000-2020 is given by = 70 + 0.50t,where t = 1 for 2000.If the annual energy consumption for 2015 was 72.5,then the percentage of trend for 2015 was:

The Pyramids of Giza The Pyramids of Giza is one of the most visited monuments in Egypt.The number of visitors per quarter has been recorded (in thousands)as shown in the accompanying table: ​ ​ -{The Pyramids of Giza Narrative} Calculate the four-quarter centered moving averages and use it to calculate the seasonal (quarterly)indexes.

One of the simplest ways to reduce random variation is to smooth the time series using moving averages and exponential smoothing.

The easiest way of measuring the long-term trend is by ____________________ analysis,where time is the independent variable.

In time series regressions the time trend component is captured using an indicator variable.

Any variable that is measured over time in sequential order is called a time series.

Liquor Sales The number of cases of liquor sold by a liquor wholesaler in an 8-year period follows. ​ ​ -{Liquor Sales Narrative} Exponential smoothing with a weight or smoothing constant of 0.4 will be used to smooth the liquor sales.The smoothed value for 2012 is_________________.

The results of a quadratic model fit to time series data were = 7.5 − 0.25t + 3.5t²,where t = 1 for 2011.The forecasted value for 2018 is:

We calculate the five-period moving average for a time series for all time periods except the:

Smoothing time series data by the moving average method or exponential smoothing method is an attempt to remove the effect of the:

Mattress Sales Monthly mattress sales (in $1,000s)of a mattress store are shown below. ​ ​ -{Monthly Mattress Sales Narrative} Compute the exponentially smoothed sales with w = 0.3 and w = 0.5.

The term "seasonal variation" may refer to the four traditional seasons,or to systematic patterns that occur during a month,a week,or even one day.

Which of the following will be reflected by deseasonalized time series?

The trend line = 500 + 30t,(t = 1,2,3,....,20),and the seasonal indexes shown in the table below were computed from five years of quarterly sales data.Forecast the sales for the next four quarters.

The trend line = 1800 + 75t− 2t² and seasonal indexes shown in the table below were computed from five years of quarterly observations.Forecast the four quarterly values for next year.

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} Plot the percentage of trend.

In time series regressions the random variation component is captured by the error term.

The linear model for long-term trend is: y = β₀ + β₁t + ε,where t is the time period.The trend is indicated by: