Talk:Life expectancy

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Contents 1 Antibiotics 2 Ambiguous and awkward statements in overview 3 Calculation of life expectancy 4 "principal determinant" is inappropriate 5 NPOV 6 NPOV?? 7 VOTE!! - HDI in country infobox/template? 8 edits by 70.251.189.154 9 average life span redirect 10 Three-score years and ten 11 Life expectancy in the Communist countries 12 Misleading expectancy after youth 13 Cats life expectancy 14 Serious Problems 15 Update 16 dog lifespan 17 Grammar Police 18 Discrepancy with history 19 the hell? 20 old age 21 gender inequality? 22 Eskimos¸ 23 Possible plagarism? 24 Edits by 138.130.191.209

[edit] Antibiotics

Don't these statistics clearly show that the biggest single impact on mortality rates occurs in the mid 20th century after the advent of antibiotics in tablet form becoming widely available?

Actually it is sanitation, leading to eliminating of cholera and other water born deaths.

[edit] Ambiguous and awkward statements in overview

The second paragraph of the overview made a claim about Hispanic versus white American life expectancy, followed by a parenthetical claim that the assertion was correct. A later parenthetical statement claimed that it "might not" still be correct in 2006. I have tried to remove some of the ambiguity and potential POV issues from the paragraph by switching to a "group A"/"group B" style presentation. dtony 21:47, 28 May 2006 (UTC)

[edit] Calculation of life expectancy

Correction to the formula, using survival curve t_p_x, we simply need to integrate it or sum it.

Sorry, I seem to have snarled up the formula - the previous one was wrong - it shd be Sigma (t * (sub_t)p(sub_x)) but my TEX is clearly wrong - can somewone put it right please?

Thanks & sorry all round.

Johnbibby 20:12, 13 November 2006 (UTC)

I changed it now. I think it should be correct. Tengfred 08:35, 14 November 2006 (UTC)

Thanks ::Johnbibby 09:51, 16 November 2006 (UTC)

Can someone add something here about how life expectancy is calculated? Could someone please explain what age-adjusted life expectancy means or how it is calculated?

Is the reduction in deaths due to war in the West included in life expectancy calculations (since the World War I, II periods)? I would assume so - jlm255

In theory, age-adjusted life expectancy for some group is the average age-of-death for that group. One could find the life expectancy for "people who turned 10 years old in 1890" by tracking down exactly when each of them died, and taking the average. "life expectancy" alone is the same as age-adjusted life expectancy for age zero -- the life expectancy for "people born in 1880" is a bit less than "people who turned 10 years old in 1890", because the first group includes all of the second group, plus a few more people (those people born in 1880 that died before age 10), and those small numbers make the average smaller.

(Would it make any sense to use the median rather than the mean ?)

In practice, we usually want the age-adjusted life expectancy for some group that *hasn't* all died yet. I imagine this is estimated using extrapolation from last-year's death rates. Could someone explain in the article: How is life expectancy really calculated? (I hesitate to write about how I imagine it is calculated). --DavidCary 05:32, 16 Jun 2005 (UTC)

---

NEOLITHIC ANOMALY: Can somebody please explain the dropoff in life expectancy for neolithic peoples? The link to Neolithic does not add any clarification, only a description of changing lifestyles. Presumably, lowered life expectancy is do to the close proximity of newly domesticated animals: the bacteria, virusus, and parasites that they harbor. I'm fairly sure this is correct, but I'm not an expert. Can somebody clarify? I think this is critical to our historical understanding of human life expectancy.

I believe it's mainly due to a poorer diet. Farmed food is poorer in nutrients than hunter/gatherer food. However, farming supports far more people per unit area, so that way of life spreads. Jared Diamond has written some good screed on this topic, see [1]WolfKeeper 19:25, 17 September 2006 (UTC)

[edit] "principal determinant" is inappropriate

Current text: "race was the principal determinant of life expectancy in the United States"

Comment: The reference cited does not use the phrase "principal determinant." It does say,“During this century gender has overtaken race as a determinant of life expectancy (non-white females out-live white males).” One could say that in the early 20th century, race was a greater determinant of life expectancy than was sex. The importance of a determinant depends on what other determinants are included. To say race was the principal determinant implies there was no greater determinant: a somewhat sweeping generalization...

[edit] NPOV

I believe this article is still in need of some NPOV editing. It fails to make very clear that a high statistical life expectancy at any one point does not imply that people are actually going to live very long, even when no unexpected catastrophes occur. As a somewhat exaggerated example, it is possible (though very unlikely) that virtually all human beings alive today will die in thirty years as a result of some degenerative disease they've already been affected with. As a more realistic example, those people (in the US) currently in their middle age have overwhelmingly had a childhood with considerably more physical exercise (and lower rates of obesity and asthma, for example) than today's children. This probably means that when the actual life expectancy (i.e. the average time they had left to live) for today's children can be calculated (i.e. when all of them have died), it might be considerably lower than what statistical life expectancy today would suggest.

Prumpf 15:12, 17 Aug 2004 (UTC)

[edit] NPOV??

Removed two paragraphs from the end of the article. They were out of place, and largely irrelevant. Anti female perspective as well. I'm new here, but if anyone has an opinion let me know.

[edit] VOTE!! - HDI in country infobox/template?

The Human Development Index (HDI) is a standard UN measure/rank of how developed a country is or is not. It is a composite index based on GDP per capita (PPP), literacy, life expectancy, and school enrollment. However, as it is a composite index/rank, some may challenge its usefulness or applicability as information.

Thus, the following question is put to a vote:

Should any, some, or all of the following be included in the Wikipedia country infobox/template:

(1) Human Development Index (HDI) for applicable countries, with year;

(2) Rank of country’s HDI;

(3) Category of country’s HDI (high, medium, or low)?

YES / NO / UNDECIDED/ABSTAIN - vote here

Thanks!

E Pluribus Anthony 01:52, 20 September 2005 (UTC)

[edit] edits by 70.251.189.154

The edits by 70.251.189.154 on 2005-10-15 were so badly written (with some pov thrown in for good measure) that I completely rewrote it. There was some sense in it, so I kept the bit about the brain being able to live up to 200 years. Does anyone know how correct this is?

Also, those life expectancies from the Encyclopaedia Britannica are very low. I assume that's caused by infant mortality. If so, that should be mentioned here too (it's mentioned above it, but that isn't enough). DirkvdM 05:37, 28 October 2005 (UTC)

[edit] average life span redirect

Life span no longer redirects here and is now a disambiguation page, in its place I have made average life span redirect here. Intangir 20:31, 5 December 2005 (UTC)

Comment: when listing lifespans for various peoples why not list at least two: from birth and from , say, age 10. This will give a clearer idea of what the differences are. http://www.ssa.gov/OACT/STATS/table4c6.html gives 67 extra years for men-women average in the U.S. as or 2005 and the site listed in the article gives 41 extra years for ancient Romans. This is less dramatic than the figures cited in the article.

[edit] Three-score years and ten

Can anyone shine light on the discrepancy between the biblical ‘three-score years and ten’ and the quoted average lifespan in classical times of 28?

Is it to do with the difference between mean (average) and mode? (e.g. more people died at 70 than at any other age). Or to do with age-adjusted life expectancy which excludes infant mortality?

I really can’t believe the Romans considered themselves on borrowed time after they were 28 (as I’m sure they did once they were past 70). Someone must have explained this conundrum, somewhere…

CDV 14:16, 19 January 2006 (UTC)

• Oops – just noticed the post above mentioning the link to Life expectancy in Roman times, which I will try to follow up on. I’d still love to know if anyone has more to offer. CDV 14:30, 19 January 2006 (UTC)

[edit] Life expectancy in the Communist countries

European communist countries (such as the Soviet Union, Poland, Czechoslovakia and Hungary) were characterized by decreasing life expectancy and increasing mortality (especially among adult men) from the late 1960s, after an initial rise after the Russian Revolution.

This is completely false, at least about Poland, but I see no reason why should it be true with other countries. Here's the data from GUS for average life expectancy in Poland:

Year	Men						Women
	0y	15y	30 lat	45y	60y	75y	0y	15y	30y	45y	60y	75y
1950	56,07	51,04	38,12	25,46	14,55	6,92	61,68	55,66	42,32	29,23	17,05	7,80
1951	55,11	50,61	37,72	25,04	14,18	6,52	60,67	55,14	41,86	28,69	16,56	7,49
1952	57,59	51,28	38,21	25,43	14,41	6,76	63,07	55,84	42,39	29,14	16,91	7,67
1953	59,58	52,71	39,28	26,08	14,75	6,87	65,05	57,16	43,20	29,64	17,19	7,78
1954	59,80	52,40	38,84	25,60	14,17	6,25	65,06	56,67	42,67	29,05	16,57	7,19
1955	60,82	53,34	39,73	26,48	15,09	7,24	66,19	57,76	43,68	30,02	17,46	8,13
1956	62,29	53,67	39,98	26,63	15,09	7,14	67,52	58,09	43,94	30,21	17,56	7,88
1957	61,20	53,04	39,39	26,10	14,55	6,84	66,70	57,69	43,54	29,82	17,17	7,62
1958	63,08	54,58	40,85	27,48	15,76	7,47	68,57	59,11	44,84	31,01	18,20	8,22
1959	62,71	54,04	40,31	26,96	15,23	7,05	68,30	58,88	44,57	30,72	17,90	7,92
1960	64,94	54,96	41,14	27,71	15,88	7,53	70,60	59,88	45,52	31,58	18,70	8,58
1961	64,91	54,77	41,03	27,60	15,80	7,67	70,78	59,98	45,58	31,61	18,72	8,74
1962	64,53	54,43	40,64	27,25	15,42	7,26	70,49	59,66	45,26	31,29	18,39	8,40
1963	65,41	54,97	41,15	27,75	15,90	7,50	71,52	60,28	45,83	31,87	18,94	8,81
1964	65,78	55,10	41,15	27,67	15,66	7,38	71,60	60,27	45,78	31,73	18,74	8,55
1965	66,58	55,48	41,52	28,05	16,05	7,68	72,40	60,64	46,13	32,05	19,04	8,77
1966	66,87	55,56	41,62	28,18	16,17	7,75	72,85	60,88	46,36	32,26	19,25	8,93
1967	66,44	55,05	41,09	27,68	15,78	7,41	72,61	60,60	46,04	31,89	18,85	8,47
1968	67,04	55,27	41,36	27,94	16,08	7,93	73,55	61,26	46,71	32,56	19,55	9,35
1969	66,50	54,78	40,82	27,41	15,62	7,59	73,09	60,82	46,26	32,12	19,15	8,91
1970	66,62	54,81	40,87	27,47	15,68	7,60	73,33	61,01	46,45	32,28	19,23	8,90
1971	66,13	53,98	40,09	26,76	14,97	6,82	73,25	60,63	46,08	31,93	18,87	8,51
1972	67,32	55,11	41,19	27,83	16,03	7,58	74,17	61,46	46,88	32,68	19,60	8,96
1973	67,15	54,75	40,82	27,47	15,76	7,32	74,30	61,40	46,82	32,61	19,52	8,89
1974	67,80	55,15	41,14	27,74	16,02	7,51	74,64	61,58	46,97	32,76	19,66	8,99
1975	67,02	54,50	40,58	27,27	15,72	7,24	74,26	61,32	46,73	32,50	19,43	8,72
1976	66,92	54,27	40,30	27,10	15,69	7,34	74,55	61,50	46,89	32,68	19,62	8,96
1977	66,49	53,93	40,05	26,91	15,63	7,20	74,50	61,50	46,91	32,69	19,67	8,97
1978	66,36	53,65	39,75	26,65	15,45	7,07	74,53	61,38	46,79	32,59	19,56	8,83
1979	66,79	53,95	40,05	26,90	15,72	7,30	74,91	61,64	47,05	32,82	19,80	9,06
1980	66,01	53,12	39,24	26,19	15,18	6,92	74,44	61,18	46,53	32,36	19,38	8,76
1981	67,10	54,18	40,26	26,99	15,79	7,49	75,24	61,92	47,30	33,09	20,07	9,41
1982	67,24	54,28	40,34	27,05	15,83	7,47	75,20	61,92	47,31	33,07	20,07	9,40
1983	67,04	53,97	40,04	26,80	15,67	7,35	75,16	61,77	47,15	32,93	19,92	9,27
1984	66,84	53,67	39,66	26,49	15,54	7,30	74,97	61,54	46,90	32,71	19,70	9,10
1985	66,50	53,26	39,21	26,04	15,14	7,04	74,81	61,31	46,65	32,46	19,49	8,98
1986	66,76	53,42	39,35	26,13	15,25	7,26	75,13	61,54	46,88	32,66	19,69	9,17
1987	66,81	53,48	39,38	26,14	15,27	7,31	75,20	61,59	46,92	32,73	19,77	9,26
1988	67,15	53,74	39,62	26,40	15,47	7,54	75,67	61,87	47,19	32,97	20,08	9,47
1989	66,76	53,33	39,34	26,21	15,42	7,55	75,45	61,79	47,13	32,92	19,92	9,45
1990	66,51	53,06	39,10	26,04	15,31	7,48	75,49	61,83	47,16	32,97	19,96	9,44
1991	66,11	52,58	38,62	25,64	15,09	7,38	75,27	61,54	46,88	32,73	19,74	9,21
1992	66,71	53,09	39,08	26,05	15,40	7,65	75,70	61,91	47,24	33,04	20,03	9,44
1993	67,37	53,67	39,56	26,36	15,48	7,63	76,00	62,14	47,44	33,20	20,10	9,41
1994	67,51	53,92	39,84	26,67	15,76	7,83	76,08	62,38	47,69	33,44	20,35	9,61
1995	67,62	53,92	39,81	26,68	15,84	7,92	76,39	62,56	47,87	33,61	20,52	9,73
1996	68,12	54,33	40,18	26,89	15,93	7,94	76,57	62,66	47,95	33,66	20,52	9,65
1997	68,45	54,46	40,35	27,10	16,13	8,15	76,99	62,94	48,23	33,91	20,80	9,87
1998	68,87	54,83	40,69	27,39	16,38	8,42	77,34	63,22	48,51	34,18	21,04	10,03
1999	68,83	54,76	40,62	27,31	16,29	8,32	77,49	63,31	48,60	34,26	21,13	10,09
2000	69,74	55,59	41,36	27,93	16,72	8,57	78,00	63,76	49,03	34,65	21,51	10,36
2001	70,21	56,02	41,77	28,27	17,03	8,81	78,38	64,12	49,38	34,98	21,80	10,55
2002	70,42	56,23	42,01	28,48	17,19	8,82	78,78	64,51	49,77	35,35	22,15	10,77
2003	70,52	56,28	42,00	28,46	17,13	8,67	78,90	64,57	49,83	35,39	22,17	10,77
2004	70,67	56,40	42,12	28,59	17,38	8,91	79,23	64,88	50,13	35,68	22,48	11,02

Taw 21:05, 26 January 2006 (UTC)

Taw, I believe your GUS table just proves the point you wanted to disprove. Look, if you consider the "Late 60's" to be years 1967-1969, you get the average LE of: 41.1 ys for 30 years old, 27.7ys for 45 years old and 15.8ys for 60 years old. The averages for years 1987-1989 (just before Poland turned non-communist) are lower in each group - 39.4, 26.3 and 15.4 respectively. So, one can conclude that during these 2 decades the LE did indeed fall for adult men in Poland.

Naapi 23 September 2006

[edit] Misleading expectancy after youth

Addressing a couple of the questions above about the discrepancy between the short life expectancy given in the article and the lifespans given in historical sources is that the "average life expectancy" of a population includes deaths of infant and children, who were in past times much more likely to die. This article needs to address this and to discuss the life expectancy of persons who live past the age of 10 or so, which is much higher than would be indicated by the misleading "average life expectancy". It might also be appropriate to incorporate data about accidents, frontier deaths, etc. - Centrx 20:46, 4 March 2006 (UTC)

[edit] Cats life expectancy

I was shocked to see that cats have a lifespans in the 20-30 year range. Is this true? I thought 15 was an old cat. Wright123 16:13, 9 April 2006 (UTC)

[edit] Serious Problems

This page has some fairly serious problems. Life expectancy in 20th Century United states was strongly affected by sewers at the turn of the century, and strongly affected by antibiotics and slightly later by vaccines in the middle of the century. While much of the improvment is due to improved infant mortality rates, there has been a strong flattening of the curve at older ages. That is, people did tend to die from bacterial infections and viruses after infancy and childhood and modern medicine did greatly reduce these causes of death. Also, roughly every 3rd line of this write up should reference a CDC publication. Chuck Simmons 04:23, 23 May 2006 (UTC)

[edit] Update

This statement may need updating: "Homo sapiens live on average 37 years in Zambia and on average 81 years in Japan."

According to the 2006 World Health Report <http://www.who.int/entity/whr/2006/whr06_en.pdf> Japan now shares the top spot with Monaco and San Marino at age 82, while Zimbabwe has dropped to 36 years. -- cybercommuter

[edit] dog lifespan

"Dogs live 10-25 years."

Is this accurate? I have never heard of a dog living 25 years. Maybe 15 years tops. Is this supposed to be for cats? Because cats can live this long.

The record is over 28 years currently. It's not that well defined.WolfKeeper 22:43, 12 July 2006 (UTC)

[edit] Grammar Police

I'm going to fix a few typos and grammar whatsits (run-ons, passive voice, etc). No plans to change context or layout in any significant way.--Legomancer 12:38, 31 August 2006 (UTC)

I think this article may need more than gentle finessing. I re-worked the introduction - keeping it simple and to the point. There is a lot of good information here, but the order/presentation is not ideal. It's kind of jumbled and stream-of-consciousness like. If nobody has any objection to the type of edits I did in the first few paragraphs, I'll standardize the entire article. Again, I don't plan to omit or change the content, just the order of some of the information and get rid of some unneeded repetition. I'll give it a few days and check back here before I do anything else.--Legomancer 13:10, 31 August 2006 (UTC)

[edit] Discrepancy with history

Can someone tell me why the lifespans on the charts seem to break with historians? I've been reading Greek and Roman poetry, and done some bit of studying on even Mongol history. The Greeks seemed to identify the "Seven Ages of Man" as being the average. They detailed each age at about a decade. This means that the ancient Greeks figured the average lifespan to be 70. Many merchants and peasants lived to be 50 and 60 (read, not excellent nutruition or healthcare). Ghenghis Kahn lived to be 65 (died of a hunting accident, not old age) and have several advisors who were into their mid-70's. Leonidas (King of the Spartans) was about 65 when he died in the Hot Gates, and many of his senior officers were well into their 50's.

So, hisotry seems to disagree with many of the accepted numbers that I hear people talk about today; and the chart given here. Can someone tell me why, or point to a source that might explain the difference?

I doubt the standard answer of "nutrition and healthcare of the rich" because even the lower classes lived to be 50 and 60 commonly.

A lot of it has to do with infant and child mortality. If you lived to be 20, you were often good to go to 60. But a lot of people didn't make it to 20, which slants the stats.

Leomarth 18:52, 18 September 2006 (UTC) \

== Upcoming merger of 'age-adjusted life expectancy' entry Giving anyone who cares a head's up about something I will most likely do in the near future. There is no such thing as 'age-adjusted life expectancy'. This is based on a gross misunderstanding of what life expectancy is. I should mention here also that the current absence of a definition of 'life expectancy' in the entry is pretty pathetic. Life expectancy is the expected remaining number of years left to be lived. To talk about life expectancy without mentioning an age is technically inaccurate. What most people here call simply life expectancy is in fact life expectancy at birth. Thus, the so-called 'age-adjusted life expectancy' is in fact just 'life expectancy'.

Summary of what I intend to do: 1- strip the 'age-adjusted life expectancy entry of its substance. Put in a rediredct and explain the nature of the misunderstanding 2- Include what's valid in that into this entry 3- Insert a first paragraph here that will contain only the definition of LE 4- Revamp the method section. Trust me ... it needs it. 5- Clean up the language (like any misuse of the word rate, probability, lifespan, and other such misconception-prone words) of the other sections, without however changing the substance

Currently accepting objections ... EpiDemog Oct 12, 2006

[edit] the hell?

"Likely extending back in time significantly, since their lives have not changed significantly. At birth: 34 At age 15: 54 At age 50: 67"

shouldn't life expectancy be the same at any age since their death age won't effect the age they are now? Or am I just an idiot?

No need to feel like an idiot, this is complicated, partly because the common usage of the term life expectancy is not exactly the same as the technical term explained here.

From the first paragraph of the article: " technically life expectancy means the expected number of years remaining to live, and it can be calculated for any age." The numbers you quote are not really life expectancy, but expected age at death for people of diffrent ages. The reason the numbers change so much is high child mortality, meaning that if you survived your childhood, you are likely to live to a fairly high age.

Hope that helps clarifying things, and if you have any suggestions for how the article should be made more comprehensible, they are welcome :-)

Tengfred 22:22, 3 December 2006 (UTC)

[edit] old age

this is retarded "In other words, even if a person never dies of disease, accident or violence, we can expect them to die of "old age" by that time."

scientifically speaking. there is no such thing as dying of "old age" —The preceding unsigned comment was added by 64.228.216.45 (talk) 03:52, 6 December 2006 (UTC).

[edit] gender inequality?

Apologies for intervening without contribution to the article, but I've recently become interested in the issue of different life expectancies for males and females. However, except for one side-sentence, this is not even mentioned in the article. According to the CIA factbook (cited in the article), the difference in life expectancy is nowhere (on a quick glance, that is) less than four years and in many places (in the western world, even) 7 years or more.

I find this aspect very important to the question of life expectancy, and the usage of "gender-neutral" mean age as inaccurate standardization that doesn't reflect reality as well as it would, were the genders separated. Just wanted to know why this subject is not at all addressed in the article.

I'm aware that neither my knowledge or skills with wikipedia are good enough to do this "addressing" myself.

regards, Mikael 84.231.110.121 10:30, 23 December 2006 (UTC)

[edit] Eskimos¸

What's the life expectancy of eskimos? 27.5 years or somewhere about 40 years? Could this info be included into article, considering they only eat meat ... --193.95.200.250 21:06, 2 January 2007 (UTC)

[edit] Possible plagarism?

This table can be found on numerous other websites using identical formatting and wording. A simple google search for "life expectancy over history" brings up most of these.

--24.20.133.212 22:54, 10 February 2007 (UTC)

[edit] Edits by 138.130.191.209

These edits appear to be random defacement... such at "Life expectancy is(about 3242546 years)"... Perhaps someone can better determine if any of the edits this person made were legitimate... IrishFBall32 03:51, 9 March 2007 (UTC)