Version 5.5.0

May 2009

Localized Language Versions

@RISK is now available in six localized languages: English, French, German, Japanese, Portuguese, and Spanish.

Speed Improvements

  • @RISK's core simulation engine now runs significantly (approximately 25%) faster than @RISK 5.0.
  • @RISK's multiple CPU capability is now enabled by default.
  • @RISK Standard and Professional Editions now will use up to 2 CPUs simultaneously.  The Industrial Edition still uses all available CPUs in the machine.
  • Models which use @RISK’s statistics functions will show major increases in speed.  A new simulation setting, "Update Statistics Functions" controls at what point during the simulation statistics functions are updated, either each iteration or the end of the simulation.

Support for Dates

@RISK now supports date formatting for defining distributions, fitting data, displaying graphs, and results.

Invalid Matrix Correction and Coefficient Adjustment Weights Matrices

@RISK has always corrected invalid correlation matrices by finding the 'closest' legal matrix to the one entered.  Now, however, @RISK allows the adjustability of each coefficient in the source matrix to be specified.  This is done with an Adjustment Weights Matrix.

Artist Distribution Window

The Artist Distribution Window has been added for defining custom distributions interactively.

Insert Function Menu and Graph

  • @RISK has a new Insert Function command which allows one to quickly insert any available @RISK function (distribution, statistic, etc.) using Excel's standard function wizard.
  • This menu includes a favorites list for quick access to commonly used @RISK functions.
  • Input distribution graphs are displayed automatically when the Excel function wizard is displayed.

New Graphing Features

  • Two new graphs are available in @RISK's Scenario Analysis: scatter plots of each scenario input vs. output (overlaid with a plot for the whole simulation) and a tornado summary of the key inputs in the scenario.
  • Scatter plots now have movable X and Y delimiters, which show probabilities of values falling in the four delimited quadrants.
  • @RISK results can now be displayed on a graph with two y-axes, showing simultaneously both probability density and cumulative probability.
  • Interesting regions of @RISK graphs can now be investigated using the new "Zooming" feature.
  • @RISK's ability to display currency symbols in graphs has been improved.
  • X-Axis tick labels can now be forced to be horizontal.

New Define Distribution Window Features

  • Alternate Parameter distributions are now in the Distribution Palette (default argument types for ALT distributions can be specified in Application Settings)
  • New favorites tab.
  • Overlays may be added and removed quickly from a new small palette

New Spreadsheet Functions

  • RiskCorrectCorrmat: Returns a corrected correlation matrix, if the input matrix is not mathematically valid.
  • RiskCorrel: Returns the correlation that returns the desired correlation coefficient (Pearson or Rank) between two simulated inputs or outputs.
  • RiskIsDate: A property function used to control date formatting for @RISK inputs and outputs.
  • RiskJohnsonSB: A bounded Johnson distribution.
  • RiskJohnsonSU: An unbounded Johnson distribution.
  • RiskJohnsonMoments: A useful distribution for modeling a distribution with a known set of moments (mean, standard deviation, skewness, and kurtosis).
  • RiskResample: Among other uses, this distribution allows a simulation output stored in the @RISK Library to be placed in Excel and sampled from in a new simulation.
  • RiskSplice: Allows the "splicing" of two different distributions together.

New @RISK VBA Control Methods

  • The new property Risk.InterfaceHidden allows the @RISK ribbon, menus, and toolbars to be hidden.
  • The @RISK Advanced Analyses can now be controlled via VBA macros.
  • The @RISK Defined Distribution Window and Browse Results Window can now be displayed via macro code.
  • The "swapping" in and out of @RISK functions can now be performed via code.
  • Many other minor additions

Expected Value during Standard Recalc Modified for Distributions with No Statistical Mean

The default "standard recalc" setting for @RISK (that is, what distribution functions will return when a simulation is not in progress) is "Expected Value."  This setting returns the expected value of each distribution function, except for a few cases where it modifies the expected value to make it more convenient for normal spreadsheet recalculation.  For example, discrete distributions will return the closest integer value to the expected value instead of the possibly non-integer true mean of the distribution.  This is done because likely the subsequent spreadsheet calculations require an integer value to work correctly.  It is possible to always return the exact expected value using the alternate standard recalc setting "True Expected Value".

In previous versions of @RISK, the following distributions would return #VALUE! for their standard recalculation expected value under certain conditions, because their mean was ill-defined or divergent:

  • Loglogistic (alpha < 1)
  • Pareto (theta <= 1)
  • Pareto2 (q <= 1)
  • Pearson5 (alpha <= 1)
  • Pearson6 (alpha <= 1)
  • Student (nu < 2)

In @RISK 5.5, these distributions will return the statistical median in those cases where the mean does not exist.  This will only occur when the standard recalculation setting is "Expected Value".  If that setting is "True Expected Value", these distributions will again display #VALUE!.

A Selection of Significant Maintenance Fixes

3731 Swapping out a distribution function that contains OFFSET function does not work correctly.

4009 Truncated RiskBinomial distribution returns incorrect 'True' EV value in spreadsheet when simulation not running.

4011 Fit report chi-squared input and fit binning labels are reversed.

4018 Auto detection of discrete vs. continuous outputs failing in some cases.

4058 Axes in thumbnails are reversed from the full-size graphs in Define Correlations Window.

4175 Lognormal MLE for certain datasets finding local maximum instead of global maximum.

4233     RiskTheoMin(RiskGamma(2,3)) returns #VALUE! instead of zero.

4325 Cumulative descending percentiles option ignored by Results Summary Window.

4333 Percentile markers on graph displayed incorrectly with cumulative descending percentiles.

4335 Quick Reports don't honor default graph formats specified in Application Settings.

4515 Summary Trend and Boxplots not displaying properly with manual number formatting in Application Settings.

4798 Cut and paste of linked fit data to another sheet causes simulation error.

4851 @RISK can not launch when Euro Currency Tool add-in is installed.

4935 CDF graph's x-axis scaling factor incorrect for Stress Analysis graphs when multiple inputs are simultaneously stressed.

5034 @RISK interferes with copy and paste between Excel and PowerPoint.

5209 Multiple simulation labels in Summary Trend Graph not displayed correct when Chart in Excel option used.

5431 Left delimiter of "Chart In Excel" graph incorrect with Excel 2007 SR2.