Quiz 18: Time Series and Forecasting

One component of a time series is cyclical variation. An example of cyclical variation is the business cycle that consists of periods of prosperity followed by periods of recession,depression,and recovery.

Episodic and residual variations can be projected into the future.

In the linear trend equation,the letter b is the average change in for each increase of one unit in t.

In a linear trend equation,t is a coded value that corresponds with a time period in a time series.

The moving average method smooths out the fluctuations in the data.

If the past data approximates a straight line,the equation used is = a + bt,where a is the Y-intercept and b is the slope of the line.

If the time series trend is nonlinear,a transformation of the data is required.

In the final step,using the ratio-to-moving-average method,the total of the 12 modified means should theoretically be equal to 12.00 because the average of the 12 months is designated as 1.00.

When estimating the specific seasonals for a monthly time series,the sum of the 12 modified means should theoretically be equal to 12.00 because the average of the 12 specific seasonals is designated as 1.00.

An analysis of past seasonal fluctuations can be helpful in planning production for items such as toys,dolls,Easter eggs,and other holiday-oriented goods.

Knowing the seasonal pattern in the form of indexes allows the retailer to deseasonalize sales. This is accomplished by dividing the actual sales for a month by the seasonal index for that month.

A typical seasonal index of 103.7 for January indicates that sales for January are below the annual average.

Autocorrelation is measured by the trend component of a time series.

The Durbin-Watson statistic is used to test for correlated residuals.

If the trend equation is = 10 + 100t,the forecasted value increases 100 units for the next time period,t.

In a time series,economic periods of prosperity followed by recession are described as a(n)________. A)secular trend B)seasonal variation C)cyclical variation D)erratic variation

In a time series,high sales in the summer and low sales in the winter is called ________. A)secular trend B)seasonal variation C)cyclical variation D)variation

The merchants in Dallas,Texas,suffered flood damage in May 2003. Stores were closed for remodeling nearly two months. What is this type of variation in sales called? A)Secular trend B)Seasonal variation C)Cyclical variation D)Episodic variation

Because a ski resort does most of its business in the winter,what is the major source of variation that affects sales? A)Secular trend B)Seasonal variation C)Cyclical effect D)Episodic effects

The following linear trend equation was developed for annual sales from 2005 to 2009,with 2005 as the base year. = 500 + 60t (in thousand $). What are the estimated sales for 2010 (in thousand $)? A)$500 B)$860 C)$1,040 D)$1,100

The following linear trend equation was developed for the annual sales of the Jordan Manufacturing Company. = 500 + 60t (in thousand $). At what rate are sales increasing? A)$60,000 per year B)$6,000 per month C)$500,000 per year D)$6,000 per year

If the least squares equation for sales data going from 2004 to 2008 is = 10 + 1.3t (in million $),what is the value of t and the forecast for 2010? A)t = 6, = 17.8 B)t = 0, = 10.0 C)t = 7, = 19.1 D)t = 6, = 0.0

What is a in the least squares trend equation? A)The intercept B)The slope C)The forecast D)The time period

What is the general equation for the logarithmic trend equation to forecast Ŷ? A)log a + log b(t) B)log at log b(t) C)at b(t) D)ab(t)

If the exports (in million $)for the period 2006 through 2010 were $878,$892,$864,$870,and $912,respectively,what are these values called? A)Moving average B)Linear trend equation C)Logarithmic trend equation D)Time-series data

What is the long-term behavior of a variable over an extended period of time called? A)Secular trend B)Seasonal variation C)Cyclical variation D)Irregular or erratic variation

A time series is a collection of data that ________. A)records past performance B)records future performance C)is limited to yearly data D)is limited to quarterly data

Why are long-range predictions considered essential to managing a firm? A)To develop plans for possible new plants B)To have raw materials available for future demand C)To develop plans for future financing D)All of these answers are correct

Which one of the following is not a component of a time series? A)Secular trend B)Moving average C)Seasonal variation D)Irregular variation

What is the correct order of events in a typical business cycle? A)Prosperity,recession,depression,and recovery B)Depression,recovery,recession,and prosperity C)Recovery,depression,prosperity,and recession D)Recession,recovery,prosperity,and depression

If a major hurricane exerts an impact on the economy,that event could be classified as a(n)________. A)secular trend B)episodic variation C)residual variation D)seasonal variation

In a linear trend equation,which variable represents the average change in the dependent variable for every unit change in time? A)a B)b C)t D)

For a time series beginning with 1991 and extending up to 2010,which year would be coded with a 1 when using the coded method? A)1989 B)1991 C)1992 D)2001

For an annual time series extending from 2000 through 2010,how many years would be lost in a three-year moving average? A)Two at the start and one at the end B)One at the start and one at the end C)Two at the start and zero at the end D)Zero at the start and two at the end

Given the trend equation, = 25 + 0.6t (base year = 2006),what would be the forecast value for 2010? A)25 B)28 C)30 D)32

How can you describe the moving average method? A)A method that smooths out a time series B)A method to deseasonalize a time series C)A technique that results in a trend-line equation D)A method for computing the slope of a trend line

For a five-year moving average,how many values will be lost at the beginning and end of the time series? A)Zero at the start and four at the end B)Three at the start and three at the end C)Two at the start and two at the end D)Zero at the start and five at the end

A linear trend equation is used to represent time-series values when the data are changing by equal ________. A)percents B)proportions C)amounts D)both percents and proportions

If time-series data are plotted on graph paper having an arithmetic scale that increases or decreases by equal percents,what type of graph will it be? A)Straight line B)Linear C)Curvilinear D)Logarithmic

What is the logarithmic transformation for the equation = a + bt? A)log a = S log /n B)log = log a + log b(t) C)log b = S(X log) /t2 D) = abt

Given a linear time-series trend = 5.2 + 3.1t,what is the forecast for 2010 if the time series started in 2003? A)23.8 B)26.9 C)30.0 D)27.7

What time-series component was exemplified during the 1980s when the American economy enjoyed a period of prosperity? A)Irregular B)Cyclical C)Trend D)Seasonal

What is an advantage of the least squares method for determining a trend line equation? A)It minimizes the error sum of squares. B)It is subject to human error. C)Forecasts have zero error. D)It is easy to calculate by hand.

A logarithmic trend equation should be used when the time-series trend is ________. A)changing in equal amounts B)increasing by equal percentages C)increasing in equal amounts D)increasing or decreasing by equal percentages

If a quarterly seasonal index is 0.56,it implies that ________. A)the quarter's sales are 56% above the yearly average B)the quarter's sales are 56% of the year total sales C)the other three quarter percentages will total 44% D)the quarter's sales are 56% of the yearly average

For quarterly seasonal indexes,the total of the adjusted quarterly indexes will equal ________. A)4.0 B)1.0 C)100% D)a variable

The range of possible values for the Durbin-Watson statistic is ________. A)any value B)any value greater than zero C)any value from zero to four inclusive D)any value less than zero

To calculate quarterly typical seasonal indexes,how many periods are included in the ratio-to-moving-average method? A)2 B)4 C)6 D)12

To calculate monthly typical seasonal indexes,how many periods are included in the ratio-to-moving-average method? A)2 B)4 C)6 D)12

To calculate monthly typical seasonal indexes,after computing the ratio-to-moving averages,the averages must be ________. A)divided by 12 B)multiplied by 12 C)summed and divided by 2 D)summed and divided by 12

To calculate monthly typical seasonal indexes,after computing the ratio-to-moving averages,the averages must be ________. A)divided by 12 B)multiplied by 12 C)summed and divided by 12 D)centered

To calculate monthly typical seasonal indexes,a specific seasonal index must be computed for ________. A)every month B)every year C)every quarter D)every day

To calculate monthly typical seasonal indexes,the specific seasonal indexes must be averaged for ________. A)every month B)every year C)every quarter D)every day

For the third quarter,the sales are 1,000 units; the seasonal index for the quarter is 1.10. What are the deseasonalized sales for the quarter? A)1,000 B)1,100 C)909 D)0.90

For the third quarter,the sales are 1,000 units; the seasonal index for the quarter is 0.85. What are the deseasonalized sales for the quarter? A)1,176 B)1,000 C)850 D)0.15

For the third quarter,the sales are 1,500 units; the seasonal index for the quarter is 1.15. What are the deseasonalized sales for the quarter? A)115% B)15% C)1,304 D)1,500

For the third quarter,the sales are 1,500 units; the seasonal index for the quarter is 0.90. What are the deseasonalized sales for the quarter? A)0.10 B)90 C)1,400 D)1,667

The forecast for the third quarter is 1,000 units; the seasonal index for the quarter is 1.10. What are the seasonally adjusted sales for the quarter? A)1,100 B)1,110 C)110 D)100

The forecast for the third quarter is 1,000 units; the seasonal index for the quarter is 0.85. What are the seasonally adjusted sales for the quarter? A)1,085 B)850 C)985 D)1,015

The trend forecast equation is = 100 + 120t. The next forecast is for period 8. The typical seasonal index for period 8 is 1.15. What are the forecast sales for period 8? A)1,060 B)1,219 C)960 D)1,075

The trend forecast equation is Ŷ = 120 + 100t. The next forecast is for period 8. The typical seasonal index for period 8 is 0.80. What are the forecast sales for period 8? A)736 B)920 C)800 D)640

The Durbin-Watson statistic is used to analyze ________. A)multicollinearity B)homoscedasticity C)autocorrelation D)variance inflation

The Durbin-Watson statistic is based on the ________. A)differences between successive residuals in a time series B)differences between successive sales in a time series C)differences between typical sales indexes D)differences in time periods

For the third quarter,the sales are 2,000 units; the seasonal index for the quarter is 1.15. What are the deseasonalized sales for the quarter? A)1,739 B)2,015 C)2,115 D)115

For the third quarter,the sales are 2,000 units; the seasonal index for the quarter is 0.80. What are the deseasonalized sales for the quarter? A)1,600 B)2,000 C)2,080 D)2,500

For the third quarter,the sales are 2,500 units; the seasonal index for the quarter is 1.20. What are the deseasonalized sales for the quarter? A)1,739 B)2,520 C)2,500 D)2,083

For the third quarter,the sales are 2,500 units; the seasonal index for the quarter is 0.95. What are the deseasonalized sales for the quarter? A)1,600 B)2,632 C)2,080 D)2,500

The forecast for the third quarter is 2,000 units; the seasonal index for the quarter is 1.18. What are the seasonally adjusted sales for the quarter? A)2,000 B)2,018 C)2,118 D)2,360

The forecast for the third quarter is 2,000 units; the seasonal index for the quarter is 0.79. What are the seasonally adjusted sales for the quarter? A)1,921 B)1,580 C)790 D)1,015

The trend forecast equation is = 100 + 120t. The next forecast is for period 11. The typical seasonal index for period 11 is 1.25. What are the forecast sales for period 11? A)1,420 B)1,775 C)1,320 D)1,075

The trend forecast equation is = 120 + 100t. The next forecast is for period 11. The typical seasonal index for period 11 is 0.82. What are the forecast sales for period 11? A)1,100 B)1,220 C)1,000 D)640

The forecast for the third quarter is 3,000 units; the seasonal index for the quarter is 1.05. What are the seasonally adjusted sales for the quarter? A)3,000 B)3,005 C)3,150 D)2,360

The forecast for the third quarter is 3,000 units; the seasonal index for the quarter is 0.75. What are the seasonally adjusted sales for the quarter? A)3,000 B)3,079 C)2,250 D)1,015

The trend forecast equation is = 50 + 420t. The next forecast is for period 10. The typical seasonal index for period 10 is 1.25. What are the forecast sales for period 10? A)4,200 B)4,250 C)5,313 D)1,075

The trend forecast equation is = 50 + 420t. The next forecast is for period 10. The typical seasonal index for period 10 is 0.82. What are the forecast sales for period 10? A)4,200 B)4,250 C)4,000 D)3,485

Which of the following components is not present in a time series? A)Secular trend B)Regular variation C)Cyclical variation D)Seasonal variation

The time-series component that exhibits fluctuations over more than a year in time above and below the secular trend is ________. A)Irregular B)Cyclical C)Seasonal D)A trend

For the following time series,you are given the 3-year moving total. The three-year moving average for 2004 is ________. A)22 B)21 C)14.33 D)166

The following trend equation is for a manufacturer of women's purses (in millions of purses)based on six years of quarterly data. = 2.15 + 1.32t The following table provides the seasonal factors for each quarter. The seasonally adjusted forecast for the second quarter of the fifth year is ________. A)25.91 B)15.35 C)29.15 D)6.8

Given the following trend equation based on five years of annual sales (in millions of dollars),beginning in 2005: = 4.53 + 1.54t The estimated value for 2008 is ________. A)9.15 B)10.69 C)12.23 D)6.07

A collection of data recorded over a weekly,monthly,quarterly,or yearly time interval is known as ________. A)a weighted moving average B)a time series C)a linear trend D)seasonal variation

In the linear trend equation,Y = a + bt,the coefficient b represents ________. A)any value of time that is selected B)the Y-intercept of the trend line C)the slope of the trend line D)the projected value at some point in time

Which of the following statements about autocorrelation are true? I. Successive residuals are often correlated in time series because an event in one time period often influences the event in the next period. II. If residuals are correlated,we can use r as the coefficient of correlation and conduct the common tests of hypothesis about regression coefficients. III. A Durbin-Watson statistic d is used,instead of directly conducting a hypothesis test on r. A)I only B)II only C)II and III D)I and III

Consider a three-year moving average. The weights given to each period are ________. A)different,with the oldest year receiving the most weight B)the same C)different,with the first year receiving the most weight D)different,with the median year receiving the most weight

The preferred method used to smooth the trend in a time series is called a ________. A)weighted moving average B)moving average C)linear trend D)deseasonalized adjustment