Length of Human Generation?

That would not be the average I would want because it would be weighted to the low side being concerned with *first* offspring. However, I still would be interested in those figures.

~~ Nehmo

For as long as I can remember, a "generation" has been regarded as 30 years. This does not necessarily take into account how young women have children, but is regarded as a grouping of people by ages.

I think maybe a "generation" is subject to people's opinions. It's always been my understanding that a generation is in 25 year intervals.

well that is my number too.. but it is interesting to read this thread, and find out all the variations.

I just became a grandfather a couple of weeks ago, so at the moment, I'm generationally average. (yes, a whole baby)

Congratulations.

That picture you have there must either be a very old one or you're a very young grandfather. Otherwise, we all want your secret to eternal youth.

The Secret!

I had the foresight to choose parents with young-looking genes!

(if only I had chosen wealthy ones too, that would have been better. )

thank you.

chris

Neither money nor good looks brings happiness. You should go for inner peace. Don't ask me how to find it.

I have innner peace... CR4!

This is a false temporary happiness.

The answer to your question is the same as what is the average age a woman has her first child. Which would change do to cultural reason to in different places.

In the USA that average was about age 21 in 1970. Today its up to over 25 years.

Here is a link to some of thoses changes in the USA.

http://www.cdc.gov/nchs/data/databriefs/db21.pdf

*first* child average age of mother is not the average of all. Maybe I can't really get the number. I have to estimate it.

~~ Nehmo

that can't be quite right, because the average size of families is 2.2 children as I recall... so it will be the number you mention, plus the average difference in age of the other 1.2 average children. approximately.

Thank God I've got a 1.0 whole child now. Would he be a 0.998 child if he lost a finger? My wife and I would like a daughter so does that mean I can start looking forward to a 0.1.....0.2.....0.3 child as pregnancy develops? regards, Leon.

no. you are just being non-average.

was I coming across as a statistician or something? I'm not even very good at math. ha.

thanks.

Average age of the children is not involve. Its first born to first born. I actuality it's the mothers age at the birth of the first daughter. We guys don't give birth so we don't count in the fact. Since we know our gender is out numbered a little your 2.2 is cut in half. maybe to 1.2. Then it's chance whether first born is male or female whats that about 50/50. You factor that up its still the average age of the mothers giving birth to their first born.

That is a really good explanation.

So it would make a difference depending on what country you're from. If average age for giving birth to a child in the Philippines is 17 then each generation there would begin every 17 years.

The number you want is the age of the father at the birth of each son and the age of the mother at the birth of each daughter. Collect perhaps 10 000 data and run a mean. You'll come up with something in the low 30s for men and high 20s for women. It has been so for some time. Here's a link for Eskimos. Interestingly, some genealogists ignore the gender of the children when computing this. It depends on your application, I suppose.

Not agree,the average age at death is called the generation period.

double not agree.

The best logical way to define the generation is to divide every century (100 years) into 4 equal period(25 years each) and then we call each of these 25 years "Generation".

Copy Right --- j.Valentino

Mexico

There is a good book, "Generations, the History of America's Future, 1584 to 2069" by William Strauss and Neil Howe (written before the 1990 elections). They discuss what might be called cultural generations, and they say history goes in four-generation, 80 year, cycles. It's a thick book and hard to summarize, but they made interesting predictions. They predicted that in the early years of the 21st century, as the wise old veterans of WW-2 are dying out, we would elect a president who had no combat experience who would get us into something really stupid, like a war with the Third World and/or economic collapse.

Its 33yr for a generation

wow... raw data on cr4 imagine that! ga.

Welcome to CR4!

chris

Thanks for the welcome.

I thought the data may be useful if the OP wanted to use their own parameters to work it out but some of the cells have moved left to take up the space of empty ones, still you live and learn.

Also Congratulations on becoming a Grandfather, we are still waiting patiently.

Paul

I appreciate you trying to help, but data of a single family is definitely weighted genetically to that line. I want the average for a large segment of the population.

Just guessing, 32 years seems rather high. At 1900 in the US the life expectancy was 50, about what it is in disadvantaged countries today.

And in Europe 200 years ago, people were lucky to get enough to eat. If you lived to 30 you were doing reasonably good. I suppose a generation back then was about 20.

~~ Nehmo

Hi Nehmo,

I agree with you about the genetic side of things, following just my male line back 7 generations, the earliest death was aged 75 and the oldest 93, the 93 year old, an agricultural labourer, was born in 1768, although it does seam to be getting less and less.

I think that 32 is probably a lot closer than you may think. As is the case in the third world today, if you lived to 5 (yes, five) you were doing really well. Once past that, you stood a good chance of living to a good age, especially if you weren't wealthy enough to eat too well. Famine and other high mortality events, usually affected the young and old most severely, and they would be too young or too old to effect the average generation period much.

Looking back to about 1800, I feel that the time between each generation is more to do with surviving to reach a child producing age and both parent being able to have children, than life expectancy. If you don't produce children, you won't effect the average generation period and large families were very common, spread over a 20 to 30 year period, thus increasing that average. If someone is the first son, of a first son of a ….first daughter, etc, they may have a generation gap of 20 years or less, but if they were a 10^th son, of a 10^th son etc. then it may be nearer 40 or even more. The vast majority of people are obviously randomly in between.

I have spent over thirty years looking thro census returns for the English Victorian Period and my family looks very, "average" with respect to size of families. To produce a Statistically accurate figure would be an astronomical amount of work for one person.

Please let me know how you get on or if I can be of any assistance.

If we can get all on CR4 interested in their family histories, and contribute data…….?,

Or you could contact the Society of Genealogists in London, they may know someone who has already done this, or where to look.

The best bet would be to pay a personal visit to their library to ask the librarians. See their web site for details.

http://www.societyofgenealogists.com

Or, if you are too far away, ask a member, like me, to visit.

Also, please excuse my ramblings.

Paul

Recently, I had a conversation in which someone, in veiled modesty, proclaimed that she had German royalty, of 200 years ago, in their family tree. I countered with the math that everybody alive has about a 1,000 (2^10 = 1,024 & GL=20yrs) ancestors going back 200 years. Therefore, she had just about everything in her family tree, and millions of people also had royalty back there. The family tree isn't much to brag about. However, the calculations become difficult when the (call it) overlap is introduced. In moder times, in developed countries, incest is discouraged. But this has not always been the case. I'll finish this later. ... Sorry, I have to go. ~~ Nehmo

I say, I say, I say...BOY! You got it all wrong.

It's 6 feet.