FO RE CAST ING
Figure 10: The four-parameter Weibull curve fit for the Non-Stop data.
Finally, Figure 10 shows the results of
one of my Excel templates that uses the
four-parameter Weibull trend curve and
uses Solver’s nonlinear programming
capability to find the optimal parameters
that minimizes the root mean square error for the entered data.
THE SURVEY
We e-mailed the vendors and asked
them to respond on our online questionnaire so readers could see the features and capabilities of the software.
The purpose of the survey is to inform
the reader of a program’s forecasting
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capabilities and features. We tried to
identify as many forecasting vendors
and products as possible and contacted
all the vendors that we identified and/
or responded to the last survey in 2012.
For those who did not respond, we tried
gentle reminders (several e-mails and
some phone calls). In addition to the
features and capability of the software,
we wanted to know what techniques or
enhancements have been added to the
software since our previous survey. The
information comes from the vendors,
and we made no attempt to verify what
they gave us.
W W W. I N F O R M S . O R G