Third video posted to our YouTube site

We have now published the third video from the first Historical Analysis Annual Conference (HAAC) to our YouTube site. It is here: (1) Data for Wargames: Lawrence – YouTube

The briefing in this third video goes for most of the video, as discussion and comments were made mostly during the briefing. The briefing ends at 55:30 the video ends at 59:27.

A few discussions of note:

At 10:10 – A discussion of what TDI does

At 18:52 – A discussion of Breakpoints

At 32:54 – A discussion of Suppression

At 37:18 – A discussion of what we don’t know

There were some issues with sound from virtual attendees, but one of these was Robert Helmbold, so, please bear with us.

The viewgraphs for these briefings were previous posted here: Presentations from HAAC – Data for Wargames | Mystics & Statistics (

The schedule for our next conference is here: Schedule for the Second Historical Analysis Annual Conference (HAAC), 17 – 19 October 2023 | Mystics & Statistics (

Bigger Fleets Win

This article just came across my desk courtesy of a friend: Bigger Fleets Win | Proceedings – January 2023 Vol. 149/1/1,439 ( 

I will avoid discussing the article, instead I will only discuss the two references to me (A little bit of vanity here).

First there is footnote 24, which references my book War by Numbers. There problem is that the discussion that he is footnoting does not something I recall writing. He may be paraphrasing me, but I do really recall making that point. Still, I appreciate the shout out.

The next paragraph also repeats footnote 24 following the sentence “Why bother discussing such ancient history when ‘everything is different now?’. I actually do not recall making such a statement, but maybe I did somewhere. Between a thousand+ blog posts, 60+ reports, 7+ books, etc. I could have said that. I don’t remember saying that. The article having two footnotes 24 and no footnote 25 leads me to suspect that the footnoting got garbled.

Later on in the article, they claim that “the DuPuy Institute finds it difficult to validate models of future combat based on past data because ‘there are no real-world examples in the past twenty-five years of combat between conventional armed forces with similar levels of advanced technology and military competence.'”

The first part of this…the “finds it difficult” part really does not sound like anything I have said. My attitude it that you go ahead and test a model to the past, because if it cannot predict the past, if it cannot predict the actions of lower tech weapons; then you can be pretty damn sure it is not also predicting modern combat. So this does not seem to be a claim I would make. 

Now the quote that is attached to that sounds exactly like something I would say or did say. I kind of remembering saying that in a phone interview. I don’t remember when or where. The reference is to footnote 30, an article on F-35s published in Breaking Defense two years ago. It is here: HASC Chair Slams F-35, 500-Ship Fleet; Highlights Cyber – Breaking Defense. Now, I don’t see any references to The Dupuy Institute there. Perhaps it is in one of the linked articles.

Anyhow, nice to be referenced and quoted. Would be nicer if it was in proper context. 

Update: Found the quote from my book. The article says:

“The Dupuy Institute, one of the most notable independent centers of operational research on land warfare, and one that models combat outcomes based on historical data, expressed this concern in 2017:

“Many have postulated… a revolution in warfare created by the synergetic effects of increased weapons accuracy… [etc., see above]. Recent U.S. conventional operations have increased this perception due to our opponents being technologically inferior, not particularly well trained, or simply incompetent, while the United States had enjoyed air supremacy and the luxury of outgunning our opponents.”

Now this is something I have said. It is footnote 29, the Freedberg article quoted above, which does not quote me. So, clearly the footnotes have gotten garbled.

I do have to thank Captain Tangredi, who I have never met, for calling us “one of the most notable independent centers of operational research on land warfare.” The quote from 2017 is clearly referring to War by Numbers (published 2017).

Wounded-to-killed ratios in Chiraq

Probably going a little astray here but was looking at reports of the number of civilians killed and wounded in the gun violence in Chicago.

It is reported that in the last 30 days, 37 people were killed and 131 were wounded. This comes out to a wounded-to-killed ratio of 3.54-to-1 or a lethality figure of 0.22. This is kind of a high wounded-to-kill ratio for direct fire weapons.

Playing with the database (see: Chicago Crime, Murder & Mayhem | Criminal Infographics | HeyJackass! | Illustrating Chicago Values) show that in 2022 there were 665 shot and killed and 2937 shot and wounded for a wounded to killed ratio of 4.42 or lethality of 0.23.

For example, in War by Numbers, pages 184-187, I have various reports from WWII of lethality of rifles of 0.32, for infantry projections of 0.30, for gunshot of 0.39, for small arms of 0.34 or 0.38 included died of wounds, of small arms in Korea of 0.26, of small arms in Vietnam of 0.49 or 0.30 including carded-for-record, of “low-velocity bullets”: in Northern Ireland of 0.08, of “high-velocity bullets” in Northern Ireland of 0.37, of bullets in 1982 Israeli-Lebanon War of 0.31, of small arms in the 1982 Israeli-Lebanon War of 0.28. Weighing all ten data sets equal: let’s say: 0.314. This is a wounded-to-killed ratio of 3.18 as caused by small arms. 

Now, a civilian environment is different that a combat zone. To start with the mix of weapons used is different. Lots of pistols, Second, the people tend to receive medical attention quicker than on a battlefield. On the other hand, some people are shot multiple times on the street, and some shootings end with a “kill shot.” Still, the wounded to killed ratio is 3.54-to-1. Of course, not sure if all the wounded are counted either. Are the wounded who do not need hospital attention counted? Are some of the wounded who need hospital attention also not counted because they choose to avoid the hospital (and the authorities)?

Artillery (fragmentation wounds) tend to have a higher wounded-to-kill ratio that wounds from gunfire (for example 0.11, 0.19, 0.27 or 0.18, 0.22 or 0.26, 0.34, 0.14 or 0.07, 0.13, 0.11 and 0.21 for an average of 0.196 or a wounded-to-killed ratio of 5.11-to-1). In convention combat, artillery tends to be the cause of the majority of wounds.

I do not know the accuracy or providence of the data I am accessing. It is discussed on the website I am referencing (Chicago Crime 2022 Archives – Criminal Infographics – HeyJackass!). Does killed only include those who are dead when they have arrived in the hospital, or does that database include those who died after they arrived (including days or weeks after they arrived)?


Thanks to Abdulelah Almarri for pointing me to the Chiraq data.

Return-to-Duty (RTDs)

I have never really done any work on RTDs. I have an entire chapter on Casualties (Chapter 15) in War by Numbers, but nothing really on RTDS.

Anyhow, more than one person has asked me about this, so let me outline what I/we know:

1). The rule of thumb Trevor Dupuy developed on RTDs was in his “Handbook on Ground Forces Attrition in Modern Warfare,” September 1986, page 90. It says:

“Finally, there is a general rule of thumb for estimating returns to duty from casualties. For each 100 personnel casualties (battle casualty, disease, or injury) 75 will be returned to duty at the end of 20 days at a rate of five per day between the 6th and 20th days after admission, and 25 will never be returned to duty as a result of death, evacuation to the Zone of the Interior, or discharge. This will vary widely from situation to situation, depending in large part upon the theater evacuation policy.”

It is also in his book Attrition, pages 53-54, stated the exact same way. We still have copies of Attrition for sale: TDI Books For Sale (

2). A report done by several people, including Ron Bellamy, who I have worked with, provides the following table:

This chart is from this report: ADA480496.pdf ( I am indebted to Alex Roslin for this research.

Note that RTDs here is those that are returned within 72 hours. So, 752,396 WIA in WWII. Of those, 20% are RTD within 72 hours (and 2.8% are DOW). For Vietnam 235,398 WIA. Of those, 35% are RTD within 72 hours (and 2.1% are DOW). Note that these RTDs within 72 hours are probably all casualties “carded for record only.”

Note that the wounded-to-killed ratio for the WWII data is 4.94-to-1 or 4.22-to-1 if DOW is counted as KIA vice WIA and 3.36-to-1 if DOW is counted as KIA and RTD is not counted as WIA. The wounded-to-killed ratio for Vietnam data is 6.15-to-1 or 5.33-to-1 if DOW is counted as KIA vice WIA or 3.43-to-1 is RTD is not counted.

For the Iraq/Afghanistan data there are 16,235 WIA. Of those, 51% were RTD within 72 hours (and 2.4% are DOW).The wounded-to-killed ratio is 12.82-to-1 or 9.61-to-1 if DOW is counted at KIA vice WIA and 4.58-to-1 is RTD is not counted.

Now, I suspect some of the figures are skewed by how casualties are counted. In World War I and II, you were counted as wounded if you spent the night in a hospital. In Vietnam at one point the U.S. Army counted 96,900 wounded and maybe 104,000 carded-for-record only, meaning over 100,000 soldiers were not counted as wounded, but were allowed to receive the Purple Heart (my father got one that way). I may need to do a blog post about “carded for record” or WIANE (wounded-in-action, not evacuated).

See our report: “C-1 Combat Mortality: Why is Marine Combat Mortality Less than That of the Army (JCS) (March 1998),” page 19. This was done as a joint project with Ron Bellamy. 

3). Now, where the “rule of thumb” that Trevor Dupuy came from is not known. In an attempt to find them, I pulled up three of the old HERO reports 1) 14. Historical Analysis of Wartime Replacement Requirements (26 July 1966), 2) 48. German and Soviet Replacement Systems in World War II (July 1975), and 3) 86. Analytic Survey of Personnel Replacement Systems in Modern War (Apil 1981).

In the second report, page 24 they do have a table “Table 3. German Replacement Army Strength, NCOs and Men, 1 September 1944” which has a total of 2,137,973 with “convalescents” making up 178.456 of that replacement army strength (8%). On 4 December 1944 (page 45) they show for November 1944 342,000 replacements of which 40,000 are convalescents (12%). And then on page 54 there are four tables, three which show convalescents. The most interesting is “Table 20: Losses and Arrivals, German Field Army. From July 1943 to March 1944.” It shows arrivals by month to the Eastern Front as 930,000, of which 421,000 are convalescents, 478,500 are replacements and 30,500 are FTDs (recruits sent to Feild Training Divisions). For “Other Fronts,” the numbers are much smaller: 24,000 convalescents and 50,000 replacements. What is interesting, but not surprising, is that the number of convalescents increase over time. From July through October 1943 it is 34,000 to 46,000 convalescents for each month, by February and March 1944 it is 60,000 convalescents a month. 

For the Russians (page 90), the Germans estimated that 200,000 Russian convalescents were returned monthly to combat as replacements. The Germans estimated (page 91) that in 1942 ten Soviets armies received 764,000 replacements. Of them, new conscripts formed 56.5% of the total, 22.5% were convalescents, 10% were from labor battalions, 9.5% had been non-combat troops, and 1.5% had formerly had occupational deferments. Over 44,000, about 6%, were former convicts, released from prions and concentration camps. 

For 1 January-31 August 1943 for sixteen Soviet armies the Germans estimated that 89% of the replacements were new conscripts, 9% were convalescents, and 2% were former non-combat and survivors of units destroyed. Also of interest is that the Germans estimated that 28% had training of less than 10 days, 49.6% had training of up to one month, and 22.4% had training of over one month. I will avoid the temptation to equate this with the current war in Ukraine.

A third report indicates that in June 1943, 34,384 Soviet replacements reached units (probably the Bryansk Army Group) facing the German Ninth Army as follows: 82% were new conscripts, 7% were convalescents, 11% were former non-combat. Their training was reported as 26% less than 10 days, 49% up to one month, and 11% were former non-combat.  

Now, none of this actually answers my questions on RTD rates, but I still found it pretty damn interesting.

Finally, there is the report “Analytic Survey of Personnel Replacement Systems in Modern War.” This last report was primarily written by C. Curtiss Johnson (in case he is reading this blog). 

It provides a few snippets of useful data. For example (page 48), it states for the 6695 and 6706 Conditional Companies (U.S. Army, Italy) that between 1 July 1944 and 10 June 1945 the two companies process approximately 12,400 patients, of whom nearly 10,400 were rehabilitated sufficiently to return to unit. This is 84% returned-to-duty.

In the case of the Vietnam War, the 90th Replacement battalion from the quarter ending 31 Jan 1969 through 31 October, processed 172,585 replacements and 175,346 returnees. Not sure this tells us much.

 But this does… to quote (starting from page C-2):

Table 20, based on data compile by the Office of the Surgeon, MTOUSA, in December 1944, shows… the sample included 71,378 patients, 29,727 of whom had been injured and 41,651 of whom were battle casualties. Of the injured patients, 26,174 or 88.05% were returned to duty after hospitalization, 799 or 2,69% died, and 2,754 or 9.26% were evacuated to ZI hospitals. Of battle casualty patients (WIA), 29,860 or 71.69% were returned to duty, 1,130 or 2.71% died, and 10,661 or 25.60% were evacuate to ZI hospitals.

Experience during 1943-1944 showed that 86.69% of injury patients who were returned to duty became General Assignment personnel, and the remainder (13.31%) became Limited Assignment. The same figures for battle casualty patients were 83.89% General Assignment personnel and 16.11% Limited Assignment personnel.  

…The General Board, ETO,… finding may be expressed in tabular form as follows:

Percentage of Returns Correlated to Theater Evacuation Policy

Days after Admission     Battle Casualties (2,090)   Non-Battle Cas. (100,000)

  60                                    50.7                                        90.6

  90                                    59.5                                        93.0

120                                    64.8                                        93.4

Of the total returned to duty, 28.6% of the battle casualties and 5.3% of the non-battle casualties were estimated to be Limited Assignment personnel. While no comparison can be made between the injuries surveyed by the Office of the Surgeon, MTOUSA, and the non-battle casualties surveyed by the General Board, ETO, the data for battle casualties in the two reports can be compared. This comparison shows that the MTO return rate (71.69%) much exceeded the greatest rate reported for the ETO (64.8%) and that the percentage of returned who became Limited Duty personnel was greater for the ETO (28.6%) than for the MTO (16.11%). The probable explanation for the disparity in these rates was the size of the populations surveyed: the ETO battle casualty sample was 2,090; the MTO sample was 41,651.

The Report of the Army’s postwar Replacement Board provides qualitative and quantitative assessments of the replacement value of hospitalized casualties. In Volume V, Annex 14, p. 1, Major General Russell B. Reynolds, who was ACS, G-1, SPA, stresses the replacement value of hospital returnees and comments:

When you sustain 10 battle casualties, you’ll bury 3, evacuate 2 to the US, find 4 suitable for return to duty in branch, and have to retrain, either in a training center, or on the job, 1. In the case of non-battle casualties, for each 10 you’ll evacuate about 4/10 of a man, bury 1/10 of a man, and find 8 2/4 suitable for return to duty in branch, and face a retraining job on 3/4 of a man. 

These numbers may be expressed on a percent basis as follows: of surviving battle casualties, 28.6% will be evacuees and 71.4% will be returnees; of surviving non-battle casualties, 4.0% will be evacuees and 96% will be returnees. It is interesting to note that when these figures are compared to the same figures derived from MTO and ETO data, there is a remarkable degree of correlation. 

The World War II data presented above may be compared to data developed from the statistical records of World War I by Colonel Albert G. Love of the US Army’s Medical Corps in 1931. Love found that in any typical group of AEF disease and non-battle injury (DNBI) patients, 3.70% would die, 7.52% would have to be evacuated (total lost 11.22%), and 88.78% would be returned to duty. For AEF battle casualty patients, excluding gas wounds, 8.12% would die, 29.58% would have to be evacuated (total lost 37.70%), and 61.88% would be returned to duty. The return rates for World War I DNBI casualties are very close to those of World War II, while World War I BC return rate is smaller than the smallest World War II BC return rate (ETO, General Board: 64.8%). The small World War I BC return rate undoubtedly reflects the less advanced medical treatment available in the earlier conflict (notice, for example, the greater percentage of BC patients dying in hospital).

Expressed in terms of AEF theater evacuation policies, Love’s data reveals the following:

Percentage of Returns Correlated to Theater Evacuation Policy

                                               Percentage Returned to Duty

Days after Admission          Battle Casualties        DNBI

  30                                        24.88                            67.40

  60                                        46.17                            81.74

  90                                        55.73                            86.38

120                                        59.53                            87.95   

…The best, most recent set of data on the replacement value of hospitalized personnel is the data developed from the Korean conflict by Frank A. Reister… Reister’s Table 13, p. 14, shows the final disposition of 248,946 US Army patients from division units originating in Korea during July 1950 – July 1953. Of this number 72,961 were battle casualties (WIA) and 175,985 were non-battle casualties. The distribution of final disposition for battle casualties originating in division units was as follows: 2.2% (1,574) died of wounds, 87.9% (64,159) returned to duty, 8.5% (6,239) were separated for disability, and 1.4% (989) wee administrative separations. The distribution of final dispositions for division non-battle casualties was as follows: 0.3% (485) died, 98.6% (173,525) returned to duty, 0.9% (1,625) were separated for disability, and 0.2% (35) were administrative separations.  

The return to duty figures developed by Reister may be compared to the same figures from Love’s compilation and the various World War II sets to indicate the relative increase in percentage of returns in the two admission categories since World War I and to underscore the value of hospital returnees as a source of replacements in future wars.

Bolding is mine. I suspect the bolded sentence was the basis of the Trevor Dupuy rule of thumb on RTDs.

In the end, there are over 140 old HERO, TNDA, DMSI and Trevor Dupuy reports. None that I have looked at clearly show where his “rule of thumb” on RTDs comes from, although it appears to have come from the last report referenced. I do have more old Dupuy files than I have time to look through them. 

4) There is probably more material out there of value. If so, please post it to the comments in this blog.

5) Proselytizing note: I really did try a couple of years ago to get a probably study done on wounded-to-killed ratios and weapon lethality over time. Could never quite get the funding. Not sure why. See: Two proposals on Combat Casualties | Mystics & Statistics (

If someone really wants the answers to these types of questions, then someone needs to start funding proper research.

Presentations from HAAC – Urban Warfare

The sixth presentation of Day 2 in the Einstein Conference Room was supposed to be virtual presentation on Artillery Suppression. This was cancelled due the presenter’s workload. Maybe next HAAC. As we had gathered all the participants back into the main conference room, I choose to skip the seventh presentation on Urban Warfare that was planned for the Einstein Conference Room. It is discussed in some depth in two chapters of my book War by Numbers. But the presentation is here: Urban I & II & III.1

This ends all the presentations for Day 2 of the First Annual Historical Analysis Annual Conference. Next will be the day 3 presentations. We are tentatively planning the next conference for 17-19 October 2023). It will be at the same locale and similarly structured.


In the Pike and Gallows Conference Center, day 2:

The first presentation of the day was my monstrosity, Iraq, Data, Hypotheses and Afghanistan (which I later turned into the book America’s Modern Wars): NIC Compilation 3.1

The second presentation of the day was Lessons Learned from Haiti 1915-1934 by Dr. Christopher Davis of UNCG: History as an Enemy and Instructor

The third presentation of the day was Estimating War Deaths (in Iraq) by Dr. Michael Spagat of Royal Holloway University of London: Iraq Deaths

We then had a group discussion on whether we could have won the war in Afghanistan. I opened the discussion with a brief 12-slide presentation, built from my original presentation that morning. It is here: Could We Have Won

This was followed by presentation by Joe Follansbee (Col. USA, ret) on a proposed Close Combat Overmatch Weapon.

The sixth presentation of the second day was Contentious Issues in Syria: the Alawi Religion, their Political Struggles, Chemical Warfare in Syria and a Hypothesized Religicide of the Alawis by Jennifer Schlacht: Alawis. Slide Deck.

The seventh presentation of the second day was The Silent Killers: A Quick Historical Review of Biological Threats by Dr. Douglas A. Samuelson: HAAC Bio Threats 09282.


In the Einstein Conference Room, day 2:

The first presentation was A Statistical Analysis of Historical Land Battles: What is Associated with Winning? by Dr. Tom Lucas of the Naval Post-Graduate School: Historical Battles what is associated with winning.

The second presentation was The Combat Assessment Technique by William Sayers: The Combat Assessment Technique.

The third presentation was Machine Learning the Lessons of History by Dr. Robert Helmbold: The Key To Victory-0017A. His supporting text is here: TEXT-0031.

The fourth presentation was Penetration Division: Theory, History, Concept by LtC. Nathan A. Jennings, PhD: HAAC Presentation_LTC Jennings.

The fifth presentation was Learning from History: The Army’s Future Study Program by LtC. Adam L. Taliaferro: HAAC_Presentation.


We had a total of 30 presentations given at the first Historical Analysis Annual Conference (HAAC). We have the briefing slides from most of these presentations. Over the next few weeks, we are going to present the briefing slides on this blog, maybe twice a week (Tuesdays and Thursday). In all cases, this is done with the permission of the briefer. We may later also post the videos of the presentations, but these are clearly going to have to go to another medium ( We will announce when and if these are posted.

The briefings will be posted in the order given at the conference. The conference schedule is here: Schedule for the Historical Analysis Annual Conference (HAAC), 27-29 September 2022 – update 16 | Mystics & Statistics (

The nine presentations given on the first day are all here: Presentations from HAAC – Air Combat Analysis on the Eastern Front in 1944-45 | Mystics & Statistics (

TLIs and Gun Control

Well, Trevor Dupuy’s work on the Theoretical Lethality Index (TLI) that was done back in 1964 has entered into the U.S. gun control debate, not by our choice.

We discussed an earlier work that addressed this at Common Use, Lineage, and Lethality | Mystics & Statistics ( This first came to our attention through an article posted by CNN that generated thousands of pingbacks to our site: Opinion: Now that guns can kill hundreds in minutes, Supreme Court should rethink the rights question | CNN.

Even though I have my doubts about the utility of using the Theoretical Lethality Index for discussing gun control, I did attend and present at the conference “Current Perspectives on the History of Guns and Society” in mid-October. See: Conference: Current Perspectives on the History of Guns and Society | Mystics & Statistics (

Attending this conference did lead to some useful discussions about collecting data on lethality and weapons effects in a civilian environment, similar in some respects to what I had in Chapter 15 (Casualties) in War by Numbers. This has been discussed before on this blog: Wounded-to-killed ratios in Ukraine in 2022 | Mystics & Statistics ( and Two proposals on Combat Casualties | Mystics & Statistics ( I am currently not actively trying to market an effort to further explore wounded-to-killed ratios in modern combat (although I think this is sorely needed) and I am not marketing any efforts to look at lethality in a civilian environment.

Now, there is an article contesting the original articles on the subject on the website The Volokh Conspiracy by David Kopel called “The Theoretical Lethality Index is useful for military history but not for gun control policy.” This blog post, which is rather long, is here: The Theoretical Lethality Index is useful for military history but not for gun control policy (

Part IV of the article actually “estimates” the TLI of an assault rifle at 640. This seems a little low. It is clear that TLIs of assault rifles are 800-900 or higher, depending on the model of the rifle and how they are calculated. David Kopel’s article provides the following figures:

18th Century Flintlock: 43
1903 Springfield bolt-action magazine-fed rifle: 495
Modern AR semiautomatic rifle: 640
Modern 9mm semiautomatic handgun: 295

Not sure why they needed to “estimate” the TLI of an assault rifle (AR), as it can be calculated using the formulae in Numbers, Predictions and War. We do have lists of various TLIs for a wide variety of weapons. We do have a complete list on the DOS version of the TNDM which I am too lazy or too busy right now to get up and running. But, we did do have some old listings and spreadsheet calculations sitting around on my computer from past model validation runs. So, let me quote some figures from those efforts:

From Excel spreadsheet:
Soviet Tula-Tokarev 33 Pistol = 297.36 (7.62mm)

Soviet AK-47 Assault Rifle = 831.685
7.92mm FG 42 Assault Rifle: 789.823
7.92mm MP 43/StG 44 Assault Rifle: 904.045

We did check back with Chip Sayers who keeps his own listings he has calculated, and they show:

Tokarev TT-33 semi-auto 7.62mm pistol – 265 
9mm Parabellum-Pistole Luger P08 – 228
9mm Walther P.38 – 229
AK 7.92mm Assault Rifle – 813
Sturmgewehr 44 – 868
Calculations vary a little from using to user depending how they determine what the practical sustained rate of fire for a weapon on a per-hour basis, maximum effective range and accuracy (often an estimation) of the weapon is (see pages 187-199 of Numbers, Predictions and War).
I guess we could go back and do the calculations for a whole range of assault rifles, but I have a lot on my plate at the moment. Certainly, someone else could do this with a little investment of time. The formulas for the TLI are public.
Anyhow, I am not going to enter this gun debate. The TLIs were designed for use in analyzing combat. While they are not directly applicable to the civilian world, they are illustrative. How relevant they are for discussions on gun control I will leave for others to argue. That is not our business.
But… there is one statement is David Kopel’s argument I must take issue with, which is “Extrapolating from the historic arms that Dupuy studies to present-day arms is questionable.”
Now, we have used the TNDM, which uses the formulae for the TLIs, as part of our effort to both analyze combat in the past and to analyze combat in the present. This construct developed in 1964 was used as part of our predictions for the Gulf War in 1991 (see: Forecasting the 1990-1991 Gulf War | Mystics & Statistics ( and Assessing the TNDA 1990-91 Gulf War Forecast | Mystics & Statistics ( and Assessing the 1990-1991 Gulf War Forecasts | Mystics & Statistics ( Needless to say, these predictions did better than most predictions at the time, and certainly did better the recent U.S. “intelligence communities” predictions for Afghanistan in 2021 or Ukraine in 2022. As I note: I like to claim that we are three-for-three in our predictions… | Mystics & Statistics ( or maybe four-for-four: Does this mean that we are four-for-four in our predictions? | Mystics & Statistics (


The TNDM was also used for part of our prediction efforts on Bosnia in 1995 (see Forecasting U.S. Casualties in Bosnia | Mystics & Statistics (, reports B-0 and B-1 here TDI – The Dupuy Institute Publications and America’s Modern Wars) and has been used for others for a number of their own efforts in 2022 (see An Independent Effort to Use the QJM to Analyze the War in Ukraine | Mystics & Statistics ( and A Second Independent Effort to use the QJM/TNDM to Analyze the War in Ukraine | Mystics & Statistics ( So, we are using TLIs for present day armies. We also did studies comparing proposed modern armor brigades with WWII armor divisions, which we have never blogged about (see FCS-1 and FSC-2 TDI – The Dupuy Institute Publications), although the corps and division-level model validation charts from that effort are in Chapter 19 (Validation of the TNDM) of War by Numbers and is reference here: Validating Trevor Dupuy’s Combat Models | Mystics & Statistics ( Some of our discussions on model validation are here: Summation of our Validation Posts | Mystics & Statistics (

But, there is also Dr. Alexander Kott’s work which extrapolates weapons developments into the future, using a set of formulas similar to the TLI. This is discussed here The Evolution of Weapons and Warfare? | Mystics & Statistics ( and here Data Used for the ARL Paper | Mystics & Statistics ( and here Data Used of the ARL Paper – post 2 | Mystics & Statistics ( and here Technological Advancement Lessons from History? | Mystics & Statistics ( and here Two ARL Reports | Mystics & Statistics ( So, if David Kopel’s statement is correct, then the work Dr. Alexander Kott is doing at the Army Research Lab (ARL) is not valid. Dr. Kott did present his work at the Historical Analysis Annual Conference (HAAC) in late September and his briefing will be posted to this blog.

Presentations from HAAC – Data for Wargames

The second presentation of the first day was given by me. It is here (45 slides): Data for Wargames (Summary) – 2. This presentation was originally prepared for a conference in Norway in December 2021. It was based upon my books America’s Modern Wars and  War by Numbers.


We had a total of 30 presentations given at the first Historical Analysis Annual Conference (HAAC). We have the briefing slides from most of these presentations. Over the next few weeks, we are going to present the briefing slides on this blog, maybe twice a week (Tuesdays and Thursday). In all cases, this is done with the permission of the briefer. We may later also post the videos of the presentations, but these are clearly going to have to go to another medium ( We will announce when and if these are posted.

The briefings will be posted in the order given at the conference. The conference schedule is here: Schedule for the Historical Analysis Annual Conference (HAAC), 27-29 September 2022 – update 16 | Mystics & Statistics (

The conference opened with a brief set of introductory remarks by me. The seven supporting slides are here: Opening Presentation

It was then followed by a briefing by Dr. Shawn Woodford on Studying Combat; The “Base of Sand” Problem: 20220927 HAAC-Studying Combat

Conference: Current Perspectives on the History of Guns and Society

I will be speaking at the Center for the Study of Guns and Society at Wesleyan University in Middleton, Conn. on 14-15 October 2022. The link to it is here: Center for the Study of Guns and Society – Wesleyan University-based center dedicated to interdisciplinary humanities study and teaching on the social and cultural history of firearms ( Click on this: Quantifying Arms Lethality in Historical Perspective – Center for the Study of Guns and Society ( Should be interesting. I have never actually attended an academic conference.

I gather the conference is open invitation:  Conference – Center for the Study of Guns and Society (

This has been discussed here before: Common Use, Lineage, and Lethality | Mystics & Statistics (

Economist Article on Urban Warfare

The Economist published an in-depth article this week on urban warfare. It is here: Armies are re-learning how to fight in cities | The Economist

You will not be able to read the entire article without a subscription, but I think I can quote the two most important paragraphs as fair use:

The biggest question is whether a lack of familiarity with city fighting has over-amplified its grim reputation. A study by Christopher Lawrence of the Dupuy Institute, which collects historical data on warfare, analysed urban operations towards the end of the second world war, including three battles over Kharkiv, a Ukrainian city which has been battered in the current conflict. It found, perhaps unsurprisingly, that cities slowed down armies: rates of advance were one-third to one-half what they were in non-urban combat.

But cities were not necessarily deadlier than other battlefields. The attacker’s casualties were no higher in urban operations than non-urban ones, and losses of vehicles were the same or lower. In more recent urban battles—those for Fallujah in Iraq in 2004 or Marawi in the Philippines in 2017—the attackers’ casualties were low, just over one death a day, and far lower than those of defenders. In fact the highest casualties in urban offensives have been borne by Soviet or Russian armies—a fact which says as much about Russian tactical prowess as it does about urban warfare.

Anyhow, thanks to the Economist for the shout-out. The three urban warfare studies that we did were done by both Richard C. Anderson and I. The first study (see: Microsoft Word – Urban Warfare Phase I _W2K_.doc ( was a joint effort by the two of us. The sections on combat stress and logistical expenditures from pages 58 to 75 was Richard Anderson’s work based upon Richard Anderson’s idea.

The second study on the three battles of Kharkov was primarily my work. The third study, which covered Manila and Hue was mostly Richard Anderson’s study. The fourth study was cancelled by Hurricane Katrina: Urban Phase IV – Stalingrad | Mystics & Statistics (

and then there is this following paragraph:

Nor does this sort of fighting seem to be uniquely traumatic (at least for those carrying guns). A report by the Rand Corporation, an American think-tank, concludes that rates of combat stress—what was once called shell shock—were no higher than usual in the battles for Brest in Brittany in 1944, Manila in the Philippines in 1945 or Hue in Vietnam in 1968 (though most civilians had, wisely, left before the fighting started). The report suggests that the intensity of urban combat paradoxically gave soldiers a greater sense of initiative, control and purpose than those fighting in open terrain. Anecdotally, Ukrainian forces facing distant and relentless shellfire in Donbas say that the inability to see the enemy is as demoralising and disempowering as anything else.

Now, this was really Richard Anderson’s work redone as a RAND study. In our first report, I put in a section called “Appendix VII: Recent MOUT Literature” (page 112-121). This was because I was appalled at what other people were claiming about urban warfare and their methodology for how they developed these ideas. While I usually try to refrain from addressing other people’s work, sometimes I can’t help myself. Anyhow, this resulted in RAND doing another study on urban warfare in 2005 called Steeling the Mind: Combat Stress Reactions and Their Implications for Urban Warfare (see: Steeling the Mind: Combat Stress Reactions and Their Implications for Urban Warfare | RAND) This effort included a section done by Dr. Todd C. Helmus (Chapter 4, pages 39-67) that was really the core of the RAND report. This effort repeated the research done by Richard Anderson. In fact, Dr. Helmus called us, and Richard ended up giving him a list of the exact NARA files we looked at. Our work is footnoted in Chapter Four the RAND study on pages 46 (along with the comment: “We would like to thank the authors of this report for their helpful comments”) and is listed in the bibliography on page 145. Otherwise, we are not mentioned, even though clearly the entire reason for their revised study was because of our study. 

Now, overall this is a good thing. We produced a report that contradicted previous RAND studies, they then conducted an independent effort to replicate our research and double-check our results. The end result is that they found our research was good and our finding were correct. This is kind of how part of the scientific process should work. 

Now, perhaps I am overly sensitive about this, but the RAND report that was published never stated up front that it was a revision of their previous work. In fact, it directly contradicted some of their previous work. Furthermore, they never stated that the basic idea for the research and the conclusions were The Dupuy Institute‘s or Richard Anderson’s. They kind of carefully avoided mentioning us other than one footnote in Chapter Four of the report. In my view, this kind of looks like they stole our ideas, claimed them as their own, and did not give us proper credit. Maybe I am truly overly sensitive about this, but this is not the first time that people at RAND have done that and this was not the last time it happened. So yea, still carrying a little bit of a grudge. Especially as before the end of 2005 I had to lay Richard Anderson off because of a lack of budget. In the end, it was our ideas, research and work, not RAND’s.

The Defensive Value of Urban Terrain

I probably should have blogged about this long ago, but you now, it is hard to stay on top of the blog and keep working on all various books that I keep signing contracts for.

Anyhow, we started getting hits on this blog from this article:  Urban Operations in Ukraine: Size, Ratios, and the Principles of War – Modern War Institute (

They specifically say:

“A military axiom is that an attacking force should outnumber defenders at the tactical level of war by a ratio of 3:1 to have a reasonable chance for success. Some analysts, including those responsible for US Army doctrine, believe a ratio as high as 6:1 is sometimes necessary to achieve success in urban operations because of the increased strength of the defense on urban terrain. Regardless of the actual requirements, force ratios are relevant for urban planners.”

This link to us is in reference to the 6:1 figure, and leads to blog post: U.S. Army Force Ratios | Mystics & Statistics (

Now, I do not know why they would use that link. I clearly am disputing the army doctrine figures with my charts from page 10 and 210 of War by Numbers:

European Theater of Operations (ETO) Data, 1944


Force Ratio                       Result                          Percent Failure   Number of cases

0.55 to 1.01-to-1.00            Attack Fails                          100%                     5

1.15 to 1.88-to-1.00            Attack usually succeeds        21%                   48

1.95 to 2.56-to-1.00            Attack usually succeeds        10%                   21

2.71-to-1.00 and higher      Attacker Advances                   0%                   42


Force Ratio…………Cases……Terrain…….Result

1.18 to 1.29 to 1        4             Nonurban   Defender penetrated

1.51 to 1.64               3             Nonurban   Defender penetrated

2.01 to 2.64               2             Nonurban   Defender penetrated

3.03 to 4.28               2             Nonurban   Defender penetrated

4.16 to 4.78               2             Urban         Defender penetrated

6.98 to 8.20               2             Nonurban   Defender penetrated

6.46 to 11.96 to 1      2             Urban         Defender penetrated


Now, my specific discussion on this is part of a three-page section on pages 209-211 called The Effect of Urban Terrain on Outcome. To quote from part of it:

The lack of any failed urban attacks is due to the favorable force ratios. The lowest force ratio of an urban attack is 1.72 to 1, and only four attacks are less than 2.00 to 1. Of the nine nonurban attacks between 1.71 and 2.00 to 1, only three failed. No attacks, urban or nonurban, executed with above 2.56 to 1 failed. There were a total of ten urban attacks made between 2.00 to 1 and 2.56 to 1 and nine nonurban attacks made in the same range. Two of the nonurban attacks in these cases failed.

This it appears that force ratios are a major factor in determining outcome. It does not appear that the difference between urban and nonurban terrain significantly influenced this result, nor can a difference be seen between rugged terrain and nonrugged terrain. Also the difference between rolling and mixed, rugged and mixed, or rugged and wooded terrain does not seem to have significantly influenced the outcomes. If a difference in the effect between rolling terrain and rugged terrain cannot be demonstrated, then the difference in effect between urban and nonurban terrain is also likely to be of the same order of effect, or less. However, the difference in terrain could affect combat power, and the difference caused by this effect could be 20 to 30 percent without it showing up in this analysis. Such small differences cannot be conclusively demonstrated given the small number of cases and the considerable variation found in this data.

Table 16.4. Summation of Force Ratios Compared to Outcomes, ETO

Force Ratio                                         Result

0.55 to 1.01 to 1.00                            Attack fails

1.15 to 2.56 to 1.00                            Attack may succeed

2.71 to 1.00 and higher                     Attack Advances


It is in the “attack may succeed” area where we may detect some differences caused by terrain effects. In the range of 1.15 to 2.56 to 1.00 we also found the statistics in table 16.5. For the urban versus nonurban cases, we found the statistics in table 16.6.

Table 16.5 Outcomes for attacks from 1.15 to 2.56 to 1.00

Cases            Attack Fails              Attack Advances             Defender Penetrated

55                   12 (21.82%)              35 (63.64%)                       8 (14.55%)


Table 16.6. Outcomes Based upon Terrain

                  Cases             Attack Fails         Attack Advances     Defender Penetrated

Urban        14                      0                         14                              0

Rolling        25                     6 (24.00%)         17                              2

Rugged       30                    6 (20.00%)          18                              6


Little can be concluded from this data, which appear to support a null hypothesis. That is, the terrain (be it urban vs. nonurban or rolling vs. rugged) has no significantly measurable included on the outcome of the battle.

Now, this is all kind of carefully worded to make sure I do not step beyond my data. Let me try to simplify this in three simple points:

  1. Urban terrain does not favor the defender more so than other terrain (rolling or rugged). In fact, it appears less. 
  2. Needless to say, the statement in the Modern War Institute article that “…ratio of 3:1 to have a reasonable chance of success” has little meaningful value. The attacker can be seen succeeding almost 80% of the time at ratios between 1.15 to 2.56 to 1. They reference the blog post that establishes this in their article.
  3. The statement that “ratio as high as 6:1 is sometimes necessary to achieve success in urban operations because of the increased strength of the defense on urban terrain” is simply out there. We did three studies on urban warfare, using more cases than anyone else has done. While we did not establish what was the defensive value of urban terrain, it clearly was not massive.