筛选结果 共找出65

A large bag of cement cost $0.80 in 20X3. The price indices are as follows.

20X3 91

20X4 95

20X5 103

20X6 106

How much does a bag of cement cost in 20X6?

A

$0.69

B

$0.85

C

$0.93

D

$0.95

Four years ago material X cost $5 per kg and the price index most appropriate to the cost of material X stood at 150.The same index now stands at 430.What is the best estimate of the current cost of material X per kg?

A

$1.74

B

$9.33

C

$14.33

D

$21.50

Over an 18-month period, sales have been found to have an underlying linear trend of y = 7.112 +3.949x, where y is the number of items sold and x represents the month. Monthly deviations from trend have been calculated and month 19 is expected to be 1.12 times the trend value.What is the forecast number of items to be sold in month 19?

A

91

B

92

C

93

D

94

Based on the last 15 periods the underlying trend of sales is y = 345.12 - 1.35x. If the 16th period has a seasonal factor of -23.62, assuming an additive forecasting model, what is the forecast for that period, in whole units?

A

300

B

301

C

324

D

325

Unemployment numbers actually recorded in a town for the second quarter of the year 2000 were 4,700. The underlying trend at this point was 4,300 people and the seasonal factor is 0.92. Using the multiplicative model for seasonal adjustment, what is the seasonally-adjusted figure (in whole numbers) for the quarter?

A

3,932

B

3,956

C

5,068

D

5,109

Monthly sales have been found to follow a linear trend of y = 9.82 + 4.372x, where y is the number of items sold and x is the number of the month. Monthly deviations from the trend have been calculated and follow an additive model. In month 24, the seasonal variation is estimated to be plus 8.5.What is the forecast number of items to be sold in month 24? (to the nearest whole number)

A

106

B

115

C

123

D

152

Which of the following are necessary if forecasts obtained from a time series analysis are to be reliable? (i) There must be no unforeseen events (ii) The model used must fit the past data (iii) The trend must be increasing (iv) There must be no seasonal variation

A

 (i) only

B

(i) and (ii) only

C

(i), (ii) and (iii) only

D

(i), (ii), (iii) and (iv)

What is the purpose of seasonally adjusting the values in a time series?

A

To obtain an instant estimate of the degree of seasonal variation

B

To obtain an instant estimate of the trend

C

To ensure that seasonal components total zero

D

To take the first step in a time series analysis of the data

The following data represents a time series:

      X        36      Y         41          34             38       42

A series of three point moving averages produced from this data has given the first two values as 38 and 39. What are the values of (X, Y) in the original time series?

A

(38, 39)

B

(38, 40)

C

(40, 38)

D

(39, 38)

sing an additive time series model, the quarterly trend (Y) is given by Y = 65 + 7t, where t is the quarter (starting with t = 1 in the first quarter of 20X5). If the seasonal component in the fourth quarter is -30, what is the forecast for the actual value for the fourth quarter of 20X6, to the nearest whole number?

A

63

B

546

C

85

D

91