Model number


A probability density function as described by a lagged normal density curve.


A probability function as described by a lagged normal density

The model presented here reproduces the JSim function generator curve well 
within certain parameter limits.  The fit is maintained at small values of RD
( > 0.004).  Significant deviations appear at larger RD values as the curve
widens and nears t.min.  Error occurs in a similar fashion as t.min
is increased and nears the curve.  The function generator drops to zero
at skew values >= 2.


The equations for this model may be viewed by running the JSim model applet and clicking on the Source tab at the bottom left of JSim's Run Time graphical user interface. The equations are written in JSim's Mathematical Modeling Language (MML). See the Introduction to MML and the MML Reference Manual. Additional documentation for MML can be found by using the search option at the Physiome home page.

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Help running a JSim model.

Bassingthwaighte JB, Ackerman FH, and Wood EH. Applications of the 
lagged normal density curve as a model for arterial  dilution curves. 
Circ Res 18: 398-415, 1966.
Key terms
lagged normal density function
probability density function
lag normal

Please cite in any publication for which this software is used and send one reprint to the address given below:
The National Simulation Resource, Director J. B. Bassingthwaighte, Department of Bioengineering, University of Washington, Seattle WA 98195-5061.

Model development and archiving support at provided by the following grants: NIH U01HL122199 Analyzing the Cardiac Power Grid, 09/15/2015 - 05/31/2020, NIH/NIBIB BE08407 Software Integration, JSim and SBW 6/1/09-5/31/13; NIH/NHLBI T15 HL88516-01 Modeling for Heart, Lung and Blood: From Cell to Organ, 4/1/07-3/31/11; NSF BES-0506477 Adaptive Multi-Scale Model Simulation, 8/15/05-7/31/08; NIH/NHLBI R01 HL073598 Core 3: 3D Imaging and Computer Modeling of the Respiratory Tract, 9/1/04-8/31/09; as well as prior support from NIH/NCRR P41 RR01243 Simulation Resource in Circulatory Mass Transport and Exchange, 12/1/1980-11/30/01 and NIH/NIBIB R01 EB001973 JSim: A Simulation Analysis Platform, 3/1/02-2/28/07.