Quantitative Methods

Question 1

Identify the major forms of time-series models (mathematical methods) used for forecasting.

Answer 1

1. Naive
2. Simple mean (average)
3. Simple moving average
4. Weighted moving average
5. Exponential smoothing
6. Trend-adjusted exponential smoothing
7. Seasonal indexes
8. Linear trend line

Question 2

Identify the major forms of causal models used for forecasting.

Answer 2

1. Regression models (linear or non-linear)
2. Input-Output models
3. Economic models

Question 3

Identify and briefly describe the major types of causal models used for forecasting.

Answer 3

Regression - uses an equation to relate a dependent variable to one or more independent variables to forecast the dependent variable.
Input-output models - describe the flow from one stage, sector, or other component to another in order to forecast values for either the predecessor or successor stage, sector, or other component.
Economic models - specify a statistical relationship between various economic quantities to forecast the value of one using the value of another.

Question 4

Identify and briefly describe major time-series patterns.

Answer 4

1. Level - data are relatively constant or stable over time
2. Seasonal - data reflect up and down swings over shot or intermediated periods of time; each swing of about the same timing and level of change.
3. Cycles - data reflect up and down swings over a long period of time
4. Trend - data reflect a steady and persistent up or down movement over a long period of time
5. Random - data reflect unpredictable