Quantitative research on demographic measurables and combat effectiveness?

[TheMarcksPlan]

I'm familiar with the large corpus on national military effectiveness... Also aware that many militaries (and virtually all modern) use anthropometric/intelligence-testing data for various purposes.

Is there any work correlating anthropometric/IQ data and combat effectiveness at large analytical levels?

The thought crossed my mind because of its potential to explain some WW2 combat effectiveness gradients. Most analysts find that Americans were generally more effective than British by war's end, for example. Systemic features of the U.S. Army surely have a role (e.g. artillery flexibility) but it's probably also relevant that America had higher living and nutritional standards. We were taller and probably had higher IQ as a result (Britain only recently caught up in height).

Similarly, Dupuy concluded- at least as of the time he wrote Genius for War - that the German/Russian combat effectiveness gradient declined in WW2 versus WW1 (at the level of bloody casualties). Surely Soviet educational improvements account for some of that.

I would guess, btw, that Americans were taller and had higher IQ's than the average German soldier, which further emphasizes the German Army's system's role in promoting military excellence.

These effects would be ameliorated by the fact that officers typically came from upper socioeconomic classes that had broadly adequate nutrition on both sides of the pond.

[Michael Kenny]

it's probably also relevant that America had higher living and nutritional standards. We were taller and probably had higher IQ as a result (Britain only recently caught up in height).

I believe c 25% of US draftees were rejected for being illiterate. No McNamara's Morons in WW2!

[TheMarcksPlan]

it's probably also relevant that America had higher living and nutritional standards. We were taller and probably had higher IQ as a result (Britain only recently caught up in height).

I believe c 25% of US draftees were rejected for being illiterate. No McNamara's Morons in WW2!

Would like to read more on that. Source? I'd be surprised if 25% met the literal definition of illiterate - were probably more like semi-literate. But would be interesting to see the details.

[Richard Anderson]

The Great Depression had a major impact on the personnel for the U.S. Army. Even my Dad, who was solidly middle class and college educated, was only 5'7" and 138 pounds when he went into the Army. When I was his age I was 5'10" and 185. Stunted growth, poor teeth, and other effects of malnutrition was endemic. The average American soldier was 5'8" and 150.5. See Bernard D. Karpinos, “Weight-Height Standards Based on World War II Experience,” Journal of the American Statistical Association, Vol. 53, No. 282, 1958, pp. 408–419.

The matter was made worse by the policy of shunting highly-educated and higher scoring IQ individuals to technical services and away from direct combat arms. Here is a good summary:

https://cgsc.contentdm.oclc.org/digital ... 4099/rec/1

[Max Payload]

Most analysts find that Americans were generally more effective than British by war's end, for example. Systemic features of the U.S. Army surely have a role (e.g. artillery flexibility) but it's probably also relevant that America had higher living and nutritional standards. We were taller and probably had higher IQ as a result

I don’t have any data to contribute but I would find it surprising if there is a correlation between height and IQ, or even, beyond a certain point, between nutrition levels and IQ.
I read recently (can’t recall the source) that in WW2 personnel (presumably white personnel) correlating the Army General Classification Test results were surprised to find that African American conscripts from the northern cities generally scored higher than white conscripts from the rural south. This outcome was not widely publicised and as late as 1979 the official line was, “The Army had introduced this test system in March 1941 as its principal instrument for the measurement of a soldier's learning ability. Five categories, with the most gifted in category I, were used in classifying the scores made by the soldiers taking the test. ... The Army planned to take officers and enlisted specialists from the top three categories and the semiskilled soldiers and laborers from the two lowest. Although there was considerable confusion on the subject, basically the Army's mental tests measured educational achievement rather than native intelligence, and in 1941 educational achievement in the United States hinged more on geography and economics than color. Though black and white recruits of comparable educations made comparable scores, the majority of Negroes came from areas of the country where inferior schools combined with economic and cultural poverty to put them at a significant disadvantage.”

From INTEGRATION OF THE ARMED FORCES 1940-1965 (DEFENSE STUDIES SERIES) Chapter 2 -
http://www.gutenberg.org/files/20587/20 ... tm#page017

[Tom from Cornwall]

Most analysts find that Americans were generally more effective than British by war's end, for example.

Some examples here would be interesting...

Systemic features of the U.S. Army surely have a role (e.g. artillery flexibility)

I'm pretty sure that the RA would disagree with any suggestion that US Army artillery was any more flexible than that of their British and Commonwealth allies.

For the British perspective, I would suggest chapter 3 of Jonathan Fennell's 'Combat and Morale in the North African Campaign' for a discussion about the 'Quality of Manpower and Morale' in the British Army @ 1942 and David French's 'Raising Churchill's Army' chapter 2 for a broader discussion of British manpower issues. Later in the war, the British Army conducted a 'grading exercise' of its infantry unit personnel and this resulted in a transfer of the lowest grades to units like the Pioneer Corps (i.e. a labour force).

When I was his age I was 5'10" and 185.

Rich,

I'm guessing that at least one of those numbers has changed since then...

Regards

Tom

[Richard Anderson]

I'm guessing that at least one of those numbers has changed since then...

Regards

Tom

Yes, I'm now 5'9". We won't get into the rest of it.

Happy New Year!

[Cult Icon]

a nation's average weight and IQ is not that correlated with "combat effectiveness". Unless they were competing on test-taking effectiveness..

IIRC the average German soldier was around 5'7'' and shorter than the American. The Japanese soldier was even shorter.

[Richard Anderson]

Audie Murphy was 5'5" and 112 pounds. Remember the old saw, "it's not the size of the man in the fight that counts; it's the size of the fight in the man". Reasonable intelligence, effective training, effective leadership, effective motivation, and combat experience were probably much more important factors.

[histan]

Got to agree with Richard, for example the Gurkhas.
Small men but outstanding combat record.

[TheMarcksPlan]

I would find it surprising if there is a correlation between height and IQ

That's not the point I'm raising but, as an aside, there is a weak but statistically significant correlation between height and IQ. https://en.wikipedia.org/wiki/Height_an ... ignificant.

The actual point is that nutritional deficit causes both height and intelligence deficits. Height is more easily measurable than intelligence. Where there's a nutritionally-related height deficit there's very likely to be cognitive deficit as well.

or even, beyond a certain point, between nutrition levels and IQ.

Beyond a certain point... The world wasn't beyond that point early last century.

Audie Murphy was 5'5" and 112 pounds. Remember the old saw, "it's not the size of the man in the fight that counts; it's the size of the fight in the man". Reasonable intelligence, effective training, effective leadership, effective motivation, and combat experience were probably much more important factors.

Got to agree with Richard, for example the Gurkhas.
Small men but outstanding combat record.

Nobody is saying short guys are bad soldiers. I'm saying (1) IQ is a relevant factor and (2) height deficits are a proxy for nutritional deficits that also impact IQ.

Doesn't seem that Richard is making this mistake but it's an error to deny the relevance of a factor because it's not always - or even often - the controlling factor. All things being equal, the side with an average IQ 3 points lower than the other is at a disadvantage. Obviously that doesn't mean that a guy with 103 IQ is the better soldier than the guy with 100 - too many other variables. A 20% correlation, for example, means that only 4% of the variance is explained by the independent variable. But a 20% correlation can give a level of statistical significance epistemically equivalent to certainty.

Setting aside math and all, this is just common sense. When I was playing football in college, for example, I knew that if I worked my butt off in the winter I might increase my strength by 10% or so. That I believed being 10% stronger would be useful did not imply that anybody 10% stronger than me could whoop me. Again too many other variables like personal ferocity. Lots of guys who could bench-press the house were worthless on the field; nonetheless on average it's better to be stronger than weaker. So too it's better to be smarter than dumber, even though the smarter guy isn't always the better soldier (and I'd probably guess a rifleman doesn't gain anything from IQ higher than 115 or so, though a staff planner/analyst generally would).

a nation's average weight and IQ is not that correlated with "combat effectiveness". Unless they were competing on test-taking effectiveness..

IIRC the average German soldier was around 5'7'' and shorter than the American. The Japanese soldier was even shorter.

If you have quantitative data showing no correlation between national IQ and combat effectiveness then you've answered my question and showed the hypothesis to be incorrect. I see no such data in your post or in easily-Googleable resources, however. Thus the question.

The US Army certainly disagrees with your suggestion that intelligence and combat effectiveness are unrelated, as the document Richard linked bemoans the lower-intelligence personnel assigned to AGF for much of the war.

If you're right that German average height was 5'7" that certainly suggests a nutritional deficit, which suggests an IQ deficit measured against the adequate nutrition case. Contemporary average German height is above 5'7", something for which there's no good explanation other than improved nutrition.

For the British perspective, I would suggest chapter 3 of Jonathan Fennell's 'Combat and Morale in the North African Campaign' for a discussion about the 'Quality of Manpower and Morale' in the British Army @ 1942 and David French's 'Raising Churchill's Army' chapter 2 for a broader discussion of British manpower issues.

Do any of these texts raise the question, "what if our boys grew up with the same nutritional standards as American boys?"

The Great Depression had a major impact on the personnel for the U.S. Army. Even my Dad, who was solidly middle class and college educated, was only 5'7" and 138 pounds when he went into the Army.

No doubt the GD had effects but probably worse effects on Britain and Germany, where the working classes had significantly lower wages than American. http://www.rug.nl/research/events/raine ... oltjer.pdf

US also had proportionately more farmers than Britain and farmers were more insulated from nutritional impacts of recessions than urbanites. My grandpa's folks were not wealthy, for example - only the GI bill got Grandpa and his brothers to college. But growing up on a dairy farm meant there was at least milk and farm produce (and game-hunting), so Grandpa is taller than his son and 5 of 6 grandsons (so far all great-grandsons are <4ft).

The matter was made worse by the policy of shunting highly-educated and higher scoring IQ individuals to technical services and away from direct combat arms. Here is a good summary:

https://cgsc.contentdm.oclc.org/digital ... 4099/rec/1

Thanks. Very interesting document. Reminds one of the US disadvantage in WW2 from not having a militarist culture (something for which we've overcompensated since then). In Germany there was immense cultural cachet to being an army guy (France probably as well) That emphasis on vocational-military translation reads like a parody of American attitudes: "The business of America is business."

Is there a similar document re Britain? (@Tom from Cornwall) The British emphasis on non-army warfare was at least as great; did the RAF/RN draw a similar proportion of the best men?

[Cult Icon]

a nation's average weight and IQ is not that correlated with "combat effectiveness". Unless they were competing on test-taking effectiveness..

IIRC the average German soldier was around 5'7'' and shorter than the American. The Japanese soldier was even shorter.

If you have quantitative data showing no correlation between national IQ and combat effectiveness then you've answered my question and showed the hypothesis to be incorrect. I see no such data in your post or in easily-Googleable resources, however. Thus the question.

The US Army certainly disagrees with your suggestion that intelligence and combat effectiveness are unrelated, as the document Richard linked bemoans the lower-intelligence personnel assigned to AGF for much of the war.

If you're right that German average height was 5'7" that certainly suggests a nutritional deficit, which suggests an IQ deficit measured against the adequate nutrition case. Contemporary average German height is above 5'7", something for which there's no good explanation other than improved nutrition.

I didn't read enough of this thread although I think one's purpose should be inch closer to practical truths rather than statistical/theoretical constructions of no practical value that helps advance one's career.

Combat effectiveness is linked towards systems, practices, morale, etc. not towards whether the troops are an inch taller, weigh 10 lbs more, got 5 more points on the IQ test and so forth. Although I will concede that the "Education" level is material as educated people are needed for the supporting services. This was an issue in the Red Army which had lower educational levels than in the West albeit their spotty Airborne forces were composed of people who graduated from the equivalent of high school.

IQ is a pretty flawed /atrocious measurement of the intellectual "worth" of a man given that the diversity of human intelligence vastly exceeds it, and certainly in say front line combat, it is not a matter of egg heads being the best fighters.

The average Japanese was about 5 foot 3 inch or 4 inch and educated comparably to the west with a further cultural upbringing of bushido. Thanks to Bushido, their performance in the island battles showed them to be the most fanatical of fighters with shockingly few prisoners. However, there were a lot of variables operating against them : eg. the systems, practices, material inferiority, their strategic situation, etc.

The average German, and American for that matter were thin men with small muscles and with stunted physical growth. WW2 movies and shows usually strike me as inauthentic as the actors are too tall and robust looking to represent those times.

[Richard Anderson]

No doubt the GD had effects but probably worse effects on Britain and Germany, where the working classes had significantly lower wages than American. http://www.rug.nl/research/events/raine ... oltjer.pdf

US also had proportionately more farmers than Britain and farmers were more insulated from nutritional impacts of recessions than urbanites. My grandpa's folks were not wealthy, for example - only the GI bill got Grandpa and his brothers to college. But growing up on a dairy farm meant there was at least milk and farm produce (and game-hunting), so Grandpa is taller than his son and 5 of 6 grandsons (so far all great-grandsons are <4ft).

I think you may be making unwarranted assumptions based upon limited data...skewed by personal experience on a post-Great Depression era dairy farm.

Recall, the Great Depression coincided with the Dust Bowl, which destroyed many farms throughout the Midwest. The first wave hit 23 states in the Ohio and Mississippi basins in 1930-1931. The second wave, the 1934 Drought, ended with Black Sunday, 14 April 1935. In 1935, 46.6 million acres of crops failed and over 130 counties lost more than half of their planted acreage. From 1933-1935, one in twenty farms were foreclosed on. The third wave, the summer of 1936, was the hottest on record. After a short respite, the heat and dry returned in 1939-1940.

The double-whammy of the Great Depression and the Dust Bowl resulted in pellagra, rickets, beriberi, and other diseases of malnutrition becoming rampant in the U.S. Jane Ziegelman and Andrew Coe explored this subject in some depth in A Square Meal, A Culinary History of the Great Depression. See also, A.R. Ruis, "'Children with Half-Starved Bodies' and the Assessment of Malnutrition in the United States, 1890–1950", in the Bulletin of the History of Medicine, Fall 2013; Vol. 87, No. 3, pp. 378-406.

The effects are also mentioned extensively by those in the U.S. Army, such as George Marshall, who directly experienced the results of malnutrition while administering the CCC and then later when attempting to build the Army. By the end of the war, 30 percent of draftees were rejected for medical reasons...for November 1940-September 1941, the period of the first draft, it was 52.8 percent. Problems with feet, teeth, eyes, and musculo-skeletal defects led the list. It got better, flat feet fell off the charts as a problem after November 1941, mostly because the standards were reduced, but dental and visual problems remained top of the list. Interestingly, visual problems were more than twice as prevalent in the World War II draft as it was in the Great War draft, auditory issues were three times more prevalent, but sadly a comparison on tooth defects was not made. See, G.St.J. Perrott, "Selective Service Rejection Statistics and Some of Their Implications", in the American Journal of Public Health, April 1946, Vol. 36, No. 4, pp. 336-342.

[Tom from Cornwall]

Do any of these texts raise the question, "what if our boys grew up with the same nutritional standards as American boys?"

No I don't think so, but then I haven't seen any evidence to show what the delta was between nutritional standards of "American boys" and those of the British Commonwealth and Empire of the time.

There is some discussion in Jonathon Fennell's 'Fighting the People's War' about the social class of British army recruits based on a systematic study carried out in October 1944 in preparation for demobolisation.

The matter was made worse by the policy of shunting highly-educated and higher scoring IQ individuals to technical services and away from direct combat arms.

Is there a similar document re Britain? (@Tom from Cornwall) The British emphasis on non-army warfare was at least as great; did the RAF/RN draw a similar proportion of the best men?

All three of the books I've recommended include references to the fact that the RN and RAF got to "skim off the cream" of the available recruits each year, leaving the British Army with what was left. I can dig out some page references if you are interested.

Regards

Tom

[Tom from Cornwall]

Also of interest for inter-war British health and diet is Martin Pugh's 'We Danced All Night: A Social History of Britain between the Wars'. As evidence of improving diet he quotes the infant mortality rate in the UK (measured in deaths for every 1,000 births up to twelve months old), p.44:

1900 - 142
1910 - 110
1920 - 82
1930 - 68
1938 - 55

Wide regional variations were noted in 1935: South-east England - 47; northern England - 68; Scotland - 76.

He also notes that these figures were 'still considerably higher than the rate in comparable countries such as the United States and Australia.'

Regards

Tom