B Data analysis and statistical techniques

Which sampling method divides the population into groups and selects from each group in proportion to its size?

• 1 Quota sampling
• 2 Stratified sampling
• 3 Cluster sampling
• 4 Systematic sampling

2,000 units cost $9,000 and 4,000 units cost $13,000. Using the high-low method, what is the estimated cost of 3,000 units?

• 1 $11,000
• 2 $10,000
• 3 $13,000
• 4 $9,000

A correlation coefficient of -0.9 indicates:

• 1 A strong positive relationship
• 2 A strong negative linear relationship
• 3 A weak positive relationship
• 4 No relationship

A regression gives a coefficient of determination (r squared) of 0.81. What does this mean?

• 1 The forecast will be 81 percent accurate
• 2 81 percent of the variation in the dependent variable is explained by the independent variable
• 3 The correlation coefficient is 0.081
• 4 The independent variable explains 19 percent of the variation

A regression line is y = 12 + 1.3x. What is the forecast for x = 60?

• 1 93
• 2 73
• 3 78
• 4 90

Monthly sales are 12, 15, 18, 15 and 21 units. What is the second three-month moving average?

• 1 18
• 2 16
• 3 17
• 4 15

The trend value for a quarter is 400 units and the additive seasonal variation is -30. What is the forecast?

• 1 400 units
• 2 12,000 units
• 3 370 units
• 4 430 units

A Laspeyres price index uses weights based on:

• 1 Base period quantities
• 2 Current period quantities
• 3 An average of both periods
• 4 Prices only, with no quantities

There is a 30 percent chance of $40,000, a 50 percent chance of $60,000 and a 20 percent chance of $100,000. What is the expected value?

• 1 $60,000
• 2 $66,667
• 3 $200,000
• 4 $62,000

The standard deviation of a data set is 12 and the mean is 60. What is the coefficient of variation?

• 1 0.2%
• 2 20%
• 3 5%
• 4 72%

Which of the five characteristics of big data describes the speed at which data is generated?

• 1 Variety
• 2 Veracity
• 3 Volume
• 4 Velocity