DATA (Analysis of time-series)
| Collection | International Encyclopedia of Systems and Cybernetics |
|---|---|
| Year | 2004 |
| Vol. (num.) | 2(1) |
| ID | ◀ 819 ▶ |
| Object type | Methodology or model |
K.De GREENE states that there are many difficulties associated with analysis of time-series data related to complex systems, as “… for example, the absence of spottiness of data, appropriate data in particular and the aggregate nature of data” (1988, p.288).
Moreover, when applied to complex cycles research: “Methods of averaging and filtering, including the selection of moving averages to eliminate the masking higher-frequency fluctuations, tend to be subjective and may produce distorted results… two kinds of errors can occur: missing the existence of a cycle or wave when it really exist, and reporting a cycle or wave when none exist (the so-called SLUTSKY effect” (Ibid).
These are the problems of practical use of FOURIER (harmonic) analysis. In a different form they also appear in the design of systems in FORRESTER's systems dynamics.