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The issue of forecast (prediction)
Databases, datamart, and data warehouses are
increasingly used in business, finance, engineering, medicine and many other fields.
They contain tons of history data which can be utilized to forecast (predict) the
future trend of the various systems, such as market forecasting, stock price prediction,
and risk management. According to an IBM research, only 7% of the corporate data are
ever used and most of them are untouched.
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Fuzzy logic combined with Fourier time series
analysis ?
Fuzzy logic works in the gray
area between "Yes" and "No." Fourier analysis is used for
component analysis or cyclic analysis of a deterministic (certain)
physical system, such as the harmonic analysis of a speech signal using a HP
spectrometer. But most practical systems involve uncertain factors
which call for special methodologies, such as fuzzy logic, to model and analyze for better
results. Examples include fluctuations of consumer prices, stock prices, and sales revenue.
Scientists at Zaptron Systems, Inc. have invented advanced technologies to combine
fuzzy logic with Fourier analysis and time series forecasting, and have built it
into the software tool base of DataX.
This theory has been validated with real-world data, and the average prediction accuracy
is 97%.
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Application Example One
(real-world data):
Problem description - We were given data of 5 consumer
prices (chicken, cucumber, eggs, beef and pork) between Jan. 1994 and Jan. 1996 for
one city in Asia . The original prices are shown in the upper-left picture below.
The goal was to use DataX to build
computer models that can accurately predict these 5 prices.
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Solution - DataX was used to perform
the following tasks: (see picture below)
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1) Principal
component analysis on each price data, giving up to 3 principal
harmonics. The upper-right picture below shows the first harmonic of each data. The
picture shows that the period of the change in the price
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a) for chicken (blue) is 11 months
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(b) for cucumber (green) is 13 months
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c) for eggs (red) is 18 months,
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(d) for beef (light blue) is 36 months (curve is edged
due to lack of consumption data), and
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(e) for pork (yellow) is 6 months
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2) Model Building
(wave analysis)- Based on the given price data (original data), DataX was used to build a
computer model for each price data separately (assuming no relationship between these 5
price data). Then these models were used to re-generate price data to validate the
models. If the re-generated data (simulated data) are close to those given, then the
model thus built is acceptable and can be used for prediction of future prices. The
lower-left picture below shows the original data and the re-generated data for chicken.
They are very close, with error (red) near 0.
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3) Forecast -
Prediction: The above models built from using DataX for the 5 consumer
prices were used to predict the future prices, and the prediction results are shown as 5 color
curves in the lower-right picture below.. The real-world data for July 1995 to
March 1996 are also displayed as black curves in the
same picture. It is shown that DataX can
produce very good prediction, with average prediction error less than 3%.
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Explanation of the 4 pictures shown below:
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Upper-left - original data for 5 commodity prices for 5
years (5 data from from history)
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Upper-right - principle component analysis (first
harmonic for each of the 5 data)
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Lower-left - build a model for each data and
reconstruct data with the models (green), error < 3%
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Lower-right - forecasted prices (color) vs. real-world
prices (black) of the 5 types of goods.
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