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John Joyce — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Black-Hawk-County, Iowa
Our Model Tree links this John Joyce across the 1920, 1930 and 1940 US Censuses in Black-Hawk-County, Iowa (XGBoost, ~Confirmed) — first a head (b.~1883), then head of a 2-person household.
Age 57
b. ~1883
Male
Head
Born: Iowa
Married
1940 Census Record Details
| Census Year | 1940 |
| Location | Black-Hawk-County, Iowa |
| Surname | Joyce |
| Given Name | John P. |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 57 |
| Marital Status | Married |
| Birthplace | Iowa |
| 1935 Residence (City) | Waterloo City |
| 1935 Residence (County) | Black Hawk |
| Additional Details | |
| Occupation | Carpenter |
| Industry | Construction |
| Class of Worker | PW |
| Hours Worked | 30 |
| Income (1939) | 2085 |
| Highest Grade | No 8 |
| 1935 Residence | Same house |
| Birth State | Iowa |
| Birth Country | United States |
| Birthplace (normalized) | iowa |
| Occupation | Carpenter |
| Township / Ward | Waterloo City |
| Est. Birth Year | ~1883 |
Household Members
Census records only state relationship to the household head.
Pairwise kinship is derived (~90–95% accurate), not recorded.
Step/blended families and boarders can break it.
2 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to John | Age | Birth yr |
|---|---|---|---|---|
| John Joyce | Head | — | 57 | ~1883 |
| James Joyce | Son | — | 21 | ~1919 |
Census Appearances
1920
Black Hawk, …
Head, age 36
Black Hawk, Iowa · implied b. ~1884 — 5 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Joyce |
| Given Name | John P. |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 36 |
| Marital Status | Married |
| Birthplace | Iowa |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Norway |
| Occupation | Carpenter |
| Industry | House |
| Class of Worker | W |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Home Owned/Rented | O |
| Home Free/Mortgaged | M |
| Birth State | Iowa |
| Birth Country | United States |
| Birthplace (normalized) | iowa |
1930
Black Hawk, …
Head, age 46
Black Hawk, Iowa · implied b. ~1884 — 5 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Joyce |
| Given Name | John |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 46 |
| Marital Status | Married |
| Birthplace | Iowa |
| Age at First Marriage | 27 |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Occupation | carpenter |
| Industry | building |
| Class of Worker | W |
| Can Read/Write | Yes |
| Home Value / Rent | No |
| Veteran | 2000 |
| Birth State | Iowa |
| Birth Country | United States |
| Birthplace (normalized) | iowa |
1940
Black-Hawk-County, Iowa
Head, age 57
Black-Hawk-County, Iowa · implied b. ~1883 — 2 household members
| Surname | Joyce |
| Given Name | John P. |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 57 |
| Marital Status | Married |
| Birthplace | Iowa |
| 1935 Residence (City) | Waterloo City |
| 1935 Residence (County) | Black Hawk |
| Occupation | Carpenter |
| Industry | Construction |
| Class of Worker | PW |
| Hours Worked | 30 |
| Income (1939) | 2085 |
| Highest Grade | No 8 |
| 1935 Residence | Same house |
| Birth State | Iowa |
| Birth Country | United States |
| Birthplace (normalized) | iowa |
Model Tree
An inferred pedigree reconstructed from census links — up to 4 generations within the 1900–1950 window. Closer generations are built from household co-residence; deeper ones are bridged by following a relative to their own childhood census. Confidence compounds and weakens with each generation.
Our Model Tree links John Joyce across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
John Joyce
Head · 1940 · age 57 · b. ~1883 · Iowa
★ You are viewing this record
Confirmed / household (~0.90+)
Probable / derived (~0.65–0.89)
Candidate (<0.65, unverified)
Original Census Page
1940 US Federal Census — Black-Hawk-County, Iowa
Open full size
1940 US Federal Census — Black-Hawk-County, Iowa
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-01140-00812)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Charles Ann Jensen | 1 | Dtr | — | Iowa |
| 2 | Berthel Jensen | 54 | Head | Owner | Denmark |
| 3 | Janine Jensen | 52 | Wife | — | Denmark |
| 4 | Mary V. Epperly | 28 | Roomer | Teacher | Iowa |
| 5 | Hilda E. Miller | 31 | Roomer | Teacher | Iowa |
| 6 | Carl H. Anderson | 51 | Head | Wood Maker | Sweden |
| 7 | Anna E. Anderson | 56 | Wife | — | Sweden |
| 8 | Bernard Corinnigan | 41 | Head | Smith-Hmr | Illinois |
| 9 | Linea Corinnigan | 33 | Wife | — | Sweden |
| 10 | Richard H. Corinnigan | 11 | Son | — | Iowa |
| 11 | William Corinnigan | 9 | Son | — | Iowa |
| 12 | Nancy Ann Corinnigan | 5 | Dtr | — | Iowa |
| 13 | Bert Douglas | 39 | Head | Police Sergeant | Iowa |
| 14 | Gertrude Douglas | 42 | Wife | — | Iowa |
| 15 | Ralph M. Blackman | 46 | Head | Fireman | Missouri |
| 16 | Zella Blackman | 43 | Wife | — | Iowa |
| 17 | Barbara Blackman | 3 | Dtr | — | Iowa |
| 18 | Velva Matson | 40 | Roomer | Bookkeeper | Iowa |
| 19 | John P. Joyce THIS PERSON | 57 | Head | Carpenter | Iowa |
| 20 | James A. Joyce | 21 | Son | — | Iowa |
| 21 | — | None | — | — | — |
| 22 | — | None | — | — | — |
| 23 | Andrew Friedl | 34 | Head | Welder | Iowa |
| 24 | Margaret Friedl | 33 | Wife | — | Minnesota |
| 25 | Milo H. Baldwin | 42 | Head | Machinist | Iowa |
| 26 | Bertha E. Baldwin | 40 | Wife | — | Iowa |
| 27 | Douglas Baldwin | 19 | Son | Checker | Iowa |
| 28 | William R. Mckelvie | 53 | Head | Train Dispatcher | Iowa |
| 29 | Alma J. Mckelvie | 49 | Wife | — | Wisconsin |
| 30 | Charles A. Mckelvie | 20 | Son | — | Iowa |
| 31 | Richard Mckelvie | 13 | Son | — | Iowa |
| 32 | John P. Brumble | 36 | Head | Fireman Repair Dept. | Iowa |
| 33 | Eda M. Brumble | 33 | Wife | — | Iowa |
| 34 | Jack H. Brumble | 12 | Son | — | Iowa |
| 35 | David A. Brumble | 9 | Son | — | Iowa |
| 36 | Michael Welbes | 76 | Head | — | Luxembourg |
| 37 | Anna M. Welbes | 69 | Wife | — | Germany |
| 38 | Josephine Welbes | 41 | Dtr | — | South Dakota |
| 39 | Mary A. Welbes | 35 | Dtr | — | Iowa |
| 40 | James P. Talbot | 23 | Roomer | Laborer | Iowa |
About This Record & Model Tree
This record was independently indexed by YourRoots from the 1940 United States Federal Census (NARA). Our Model Tree links this person across census decades using XGBoost-based record linkage, with per-link confidence scores. Household corroboration strengthens the signal when co-residents appear on the same census pages in multiple years.
Source: National Archives and Records Administration (NARA)