How long is each generation in your family? [Updated]

Question

I made an app inspired by this r/genealogy post, and thought maybe I'd post about it here.

It calculates some stuff about your ancestor's birth years and the length of time between each generation.

https://apps.wikitree.com/apps/nelson3486/stats/

Edit: It now also shows you the average lifespan.

Comments

How long should I wait for an answer?  The meter cycles through the numbers and then goes blank.

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Ok, it worked. I had to log out and log back in.

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Average 32.

Range 28 - 37.

Median 31

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That's awesome, Jamie! I love this.

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In my line I think it would be around 70.

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Still waiting for calculation, & only have about 30 ancestors so far.  Same problem as Michael Stills, but logging out/in from Wikitree doesn't help.  Neither does closing my window & starting fresh.  Neither does changing servers (tried Chrome & Firefox).

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Could it be listed here, so we can find it easier in the future??

https://www.wikitree.com/wiki/Help:Apps

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Thanks! I'm not sure it allows for all of the endogamy in my family tho....

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My average is 31 years.

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Mine is average of 35 years.  I have a daughter who was 8 months old at her brother’s 21 birthday party.

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Thank you!  I’ve wondered about 25 years being considered a generation.  My relatives always seemed to be much older.  My average - 32 years.

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Average generation length: 33

Average lifespan: 69

Answer 1

When I set up the table at https://www.wikitree.com/wiki/Smith-62120#Status_of_Ancestry_Information I looked at the ranges of decadal dates for the ancestors in each generation and put those ranges in the table (possibly omitting a few extreme outliers). I probably have more data now, but the information is probably still mostly good. It looks to me like 30 years is a pretty good estimate of the overall average spacing between generations.

Your app gives me pretty much the same result. Over 10 generations, it found an average of 31 years. For individual generations, the length varied from 29 to 33.

Comments

I wondered why I seem to have less ancestors than many I have looked at as far as going back to a particular time and place and my family had really long generations - I have four different ones about 40 years and one that is 52 years - now both my parents are the youngest of ten and several of the grands are last of big batches too - so we just roll that way in my family I guess - I did not start having my kids until I was 26 and had the last one at age 43, so I am carrying on in that tradition too - crazy!

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Mine appears to average about 30, as well. It's also interesting to see that by the time I get to my 7x-grandparents, some of them were born in the 1660s and some were born in the 1750s, almost a hundred years later!

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My 7x-grandparents show birth dates ranging from 1620 to 1724 -- more than a century. When we go that many generations back, I imagine that a 100-year spread in dates is probably pretty typical.

Answer 2

What an interesting app!

I was not surprised to see the average of 35 years. Both grandparents and great grandparents average 40 years.

Descending from the youngest child born to a mother in her 40s has made for an interesting discussion with nth cousins who match via DNA and insist we must have missed a generation.

Comments

It's not unusual to look at censuses and find women having babies well past 40. Thus the phenomenon of nieces and nephews being older than some of their aunts and uncles!

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See now I have that here - Emily, my youngest is five months younger than my oldests first child - we were all pregnant that summer - the dog, the cat and both of us!  They are in the same class - now sophomores in our tiny school in our tiny town - so My youngest is Aunt to my oldest grandaughter -

I was from the youngest in moms family - so all my cousins are way older

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I too have an average of 35, with a spread of 28 to 50.  I have both a 28 and 29, and a 49 and 50.  My grandmother was the youngest of 15, and she was told by her mother that she too was the youngest of 15.

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Mine average 37 - quite long it looks like - longest 58 - 7th ggparents are 28, so if you are having these longer generations that would mean with the older parents you would have had those people raised by older parents and in many cases one or both parents have passed so raised by sisters, brothers or other family - Interesting

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As the 7th child of a third marriage for my father born the year he turned 63, this discussion of generational length of of interest. Going back 10 generations on my father's side the gaps are 63, 35, 31, 30, 51, 33, 37, 47, 34, 25. This ends up with my 8th great grandfather born in 1564, William Skipwith, MP. This is a 38.6 year generational gap. My teacher didn't believe me when I said my father served in WWI, and I know she wouldn't have believed me when I said my grandfather was born 9 years before the Civil War.

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That's really interesting, Susan! I'd love to see you enter your ancestry in WikiTree so you can show off those family members -- and use the nifty app that Jamie created. (Your profile at https://www.wikitree.com/wiki/Cannell-186 doesn't have any family yet...)

Answer 3

My mom is 70 my grand mom is 90 so o went with 70ish

Answer 4

Very cool app. Let's see....

Average generation length is 30. Not bad. It ranges from 24-32.

Answer 5

Awesome app. 

Average generation length: 28

Answer 6

Jamie: I just tried it out, it's a really great tool!

Answer 7

I updated the app so it now shows the average lifespan of each generation, and the total average lifespan.

Comments

Love the app.  Just tried it again including average lifespan and am confused. Could you explain number on average lifespan? My parents show as   -919, for 5th ggp  -11, and 7th ggp as  -193.  Total average lifespan is  -77.  I doubt those are supposed to be negative numbers., but I'm not sure what they do mean.

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Yeah, they shouldn't be negative numbers. I'll have to figure out what is going wrong with your dates.

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Can you run https://apps.wikitree.com/apps/nelson3486/dev/stats/ and copy/paste the text below the table with all the numbers?

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Self0

Parents82, -1920
Grandparents52, 74, 105, 93
Great-Grandparents55, 51, 72, 53, 77, 77, 60, 68
2x Great-Grandparents63, 84, 82, 68, 72, 87, 58, 88, 57, 71, 80, 21, 78, 90, 43, 66
3x Great-Grandparents74, 61, 79, 83, 70, 68, 93, 55, 52, 75, 81, 85, 70, 79, 63, 78, 71, 31, 70, 51, 56, 62, 70, 71, 45, 86, 88
4x Great-Grandparents74, 80, 42, 78, 78, 71, 100, 100, 80, 66, 46, 43, 59, 64, 59, 64, 76, 76, 45, 55
5x Great-Grandparents56, -1730, 62, 63, 70, 48, 74, 72, 72, 95, 49, 64, 82, 95, 49, 64, 82, 58, 84, 51, 69, 43, 64
6x Great-Grandparents70, 69, 70, 69, 74, 78, 71, 61, 61, 60, 79, 56, 0, 71, 61, 61, 60, 79, 56, 0, 74, 43, 52, 54, 81, 105, 83, 63, -1720
7x Great-Grandparents46, 63, 46, -1681, -1681, 62, 55, 62, 63, 73, 84, 95, 69, 91, 62, 48, 50, 62, 63, 73, 84, 95, 69, 91, 62, 48, 50, 53, -1690, -1693, -1701, 52, 44, 60

Average generation length: 31

Average lifespan: -77

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Try https://apps.wikitree.com/apps/nelson3486/dev/stats/ again?

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Thanks so much Jamie.  It works like a charm now.

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Just one more quick question.  It appears to me that if one parent is still living their data is not included in the calculations.  So the average lifespan for the parents is actually using the age at death of the one deceased parent for the average.  Is that correct?

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Yep. I could update it to include the living as well.

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I use this link and it shows me at 77. I am not 77. Earliest birth year is 1908.  My birth year is not 1908.

I use the link at the top of this post and get the correct inlormation. 

Just thought I would let you know.

Self77
Parents62, 64
Grandparents92, 69, 72
Great-Grandparents80
2x Great-Grandparents
3x Great-Grandparents
4x Great-Grandparents
5x Great-Grandparents

Average generation length: 30

Average lifespan: 75

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Right, the link in this comment chain is the dev version. Right now it is using someone else's data.

Answer 8

I like seeing these statistics. I've never seen anything like this before

Answer 9

Love this cool app Jamie.  Thanks for creating it.  I was just a bit surprised by the new average life span stats for my branch of the tree.  It was 69 for my 4x great grandparents and 66 for my 7x.  People lived much longer than I was "taught" in school.  I have sources that show that my 7x great grandmother Waite Sherman lived to be 90 years old and she had 10 children.  That is amazing to me.

Answer 10

Average lifespan:  63 years.

I'm 62.  My birthday is in four months. 

Comments

So according to Jamie, your time is almost up!?!   

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Not Jamie's fault, but I believe my time ain't long.