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Dr. Frederick W. Lanchester. Fitting Lanchester Models to the Battles of Kursk (and Ardennes) by Tom Lucas, Turker Turkes, Ramazon Gozel, John Dinges Naval Postgraduate School, Monterey CA. Outline. Overview of the Battle of Kursk
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Dr. Frederick W. Lanchester Fitting Lanchester Models to the Battles of Kursk (and Ardennes)byTom Lucas, Turker Turkes, Ramazon Gozel, John Dinges Naval Postgraduate School, Monterey CA
Outline • Overview of the Battle of Kursk • Some Previous Research on Fitting Lanchester Equations to Battle Data • Lanchester and the Battle of Kursk (and Ardennes) • More details are in the students’ theses and two summary papers
The Battle of Kursk “This attack is of decisive importance. It must succeed, and it must do so rapidly and convincingly. It must secure for us the initiative for this spring and summer. The victory of Kursk must be a blazing torch to the world.”—Hitler, 2 July 1943
CumulativePersonnelCasualties Field Marshal Erich von Manstein: “The last German offensive in the East ended in a fiasco, even though the enemy…suffered four times their losses.”
Outline • Overview of the Battle of Kursk • Some Previous Research on Fitting Lanchester Equations to Battle Data • Lanchester and the Battle of Kursk (and Ardennes)
Dr. Frederick W. Lanchester Lanchester’s equations: The most important model of combat?
Bracken’s Generalized Homogeneous Lanchester Model • If p = 1 and q = 0 Square law • If p = 1 and q = 1 Linear law • If p = 0 and q = 1 Logarithmic law
Validation Efforts:Before and After Battle Data • Lots of efforts • Osipov (1915), Willard (1962), Weiss (1966), Fain (1977), Peterson (1967) • Contradictory findings • Schneider (1985): “At best, one can say that the results of these studies have been contradictory” • Hartley’s (2001) conclusions • “The homogeneous linear-logarithmic (p = .45, q = .75) Lanchestrian attrition model is validated to the extent possible with current initial and final size data.” • “Two-sided daily attrition data on a large number of battles are needed to absolutely confirm these results.”
Validation Efforts:Time-phased Battle Data • Iwo Jima • Engle (1954) • Inchon-Seoul • Busse (1971), Hartley and Helmbold (1995) • Ardennes • Bracken (1995), Fricker (1998), Wiper et al. (2000)
Outline • Overview of the battle of Kursk • Some Previous Research on Fitting Lanchester Equations to Battle Data • Lanchester and the Battle of Kursk (and Ardennes)
Pair-wise Scatter Plots on Combat Power and Combat Power Losses
Three Kursk Data Sets:Manpower Averages as a Function of Unit Status
Approach to Finding Best-fitting p and q • Find best-fitting response surface as a function of p and q • Given p and q, it turns out to be relatively easy to find a, b, and d to minimize SSR • For a fixed d, solve for a and b by regression through the origin • Through a one-dimensional line search on d, we find the d, and associated a and b, that minimize SSR for the given p and q
Kursk ACUD Surface(Bracken’s Weights) * With d (= 1.028), R2 = 0.238 R2 = 0.237
Kursk ACUDChange Points: Four Different d’s • 8 parameters with 14 days of data • * = different SST
x x x x x x The best-fitting Lanchester law is p = 1.156 and q = 1.000, with an R2 of .624. Kursk Manpower Fits as a Function of Contact Status
Assessing the Model Fit A comparison of the estimated losses (Soviets = SLest and Germans = GLest) with the actual losses (Soviets = SLact and Germans = GLact) for the best fitting constant attrition coefficient Lanchester linear law using the FCUD data
Ardennes Basic Lanchester ModelsBracken’s formulation (10 days)
Ardennes 10 Day Surface • Square law fits best • p* = .9, q* = -.6, d* = 1.125 R2 = 0.380
Fricker’s 32 day Surface • Logarithmic law fits best • p* = -.2, q* = 5.0, d* = 1.23 R2 = 0.500
Conclusions • Much better fits are obtained with Fighting Units only • The data provide no conclusive differentiation among the basic Lanchester models (though Linear and Logarithmic better than Square) • Much more of the variation in casualties is explained by the phases of the battle