The underlying
WebFOCUS language has a built-in statistical function that can perform some
basic predictive analytics. If you only need basic data forecasting, there may
be no need to purchase a third-party statistical product.
Out of the box,
WebFOCUS supports the following forecasting functions:
- Linear Regressions
- Simple Moving Averages
- Exponential Moving Averages (single, double, and triple)
Using linear
regression, a WebFOCUS application can calculate a straight line that best fits
a time-series of actual data points. The predictions are then future points
along this straight line past the available actual data values.
A moving average is
commonly used with a series of data spread over a time period to identify
long-term trends or to smooth out short-term fluctuations. You might also know
this as a rolling average, rolling mean, or running average. The WebFOCUS
application tells the forecasting function how many data values to use when
calculating the averages.
A simple moving
average calculates averages using the actual data values. For an exponential
moving average, the function calculates a weighted moving average using an
actual data value and its previously calculated average. The weighting factors
decrease exponentially over time, never reaching zero.
In a single
exponential moving average (also known as smoothing), the WebFOCUS application
applies multipliers (weights) to the newer and older values. However, this
technique may not accurately identify real trends in the data series. To better handle true data trending, the
WebFOCUS function provides for both double and triple exponential moving
averages.
In a double
exponential moving average, weighting accounts for the tendency of data to
either increase or decrease over time without repeating. In a triple
exponential moving average, weighting accounts for repeated seasonal
fluctuations in the data in addition to the trend.
You can read more
about this on Information Builders' documentation site.
It your BI application
needs only the basic forecasting methods using linear regression, simple moving
averages, or exponential moving averages, WebFOCUS may already have the
features you need. If however you need more robust analytics, then implementing
industry-strength statistical products such as the open source R language,
IBM's SPSS, SAS, or KXEN may be more appropriate than using the standard
WebFOCUS forecasting function.
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