JD
John Duffy — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Allegheny-County, Pennsylvania
Our Model Tree links this John Duffy across the 1920, 1930 and 1940 US Censuses in Allegheny-County, Pennsylvania (XGBoost, ~Confirmed) — first a head (b.~1887), then head of a 4-person household.
Age 53
b. ~1887
Male
Head
Born: Scotland
Married
1940 Census Record Details
| Census Year | 1940 |
| Location | Allegheny-County, Pennsylvania |
| Surname | Duffy |
| Given Name | John J. |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 53 |
| Marital Status | Married |
| Birthplace | Scotland |
| 1935 Residence (City) | Pittsburgh |
| 1935 Residence (County) | Allegheny |
| Naturalization Status | Naturalized |
| Additional Details | |
| Occupation | Foreman |
| Industry | Railway |
| Class of Worker | PW |
| Hours Worked | 48 |
| Income (1939) | 2500 |
| Highest Grade | Hs 4 |
| 1935 Residence | Same place |
| Birth Country | Scotland |
| Birthplace (normalized) | scotland |
| Occupation | Foreman |
| Township / Ward | Pittsburgh |
| Est. Birth Year | ~1887 |
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.
4 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to John | Age | Birth yr |
|---|---|---|---|---|
| Helen Hart | Daughter | — | 26 | ~1914 |
| John Duffy | Head | — | 53 | ~1887 |
| William Weber | Other | — | 26 | ~1914 |
| Mildred Duffy | Spouse | — | 44 | ~1896 |
Census Appearances
1920
Allegheny, Pennsylvania
Head, age 38
Allegheny, Pennsylvania · implied b. ~1882 — 2 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Duffy |
| Given Name | John J |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 38 |
| Marital Status | Single |
| Birthplace | Scotland |
| Year of Immigration | 1883 |
| Naturalization Status | Naturalized |
| Father's Birthplace | Scotland |
| Mother's Birthplace | Scotland |
| Occupation | Conductor |
| Industry | Railroad |
| Class of Worker | W |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Mother Tongue | Scotch |
| Home Owned/Rented | R |
| Birth Country | Scotland |
| Year of Naturalization | 1893 |
| Birthplace (normalized) | scotland |
1930
Allegheny, Pennsylvania
Other, age 45
Allegheny, Pennsylvania · implied b. ~1885 — 7 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Duffy |
| Given Name | John |
| Relationship to Head | Boarder |
| Sex | M |
| Color / Race | White |
| Age | 45 |
| Marital Status | Single |
| Birthplace | Scotland |
| Naturalization Status | Naturalized |
| Year of Immigration | 1885 |
| Father's Birthplace | Scotland |
| Mother's Birthplace | Scotland |
| Occupation | Janitor |
| Industry | Public School |
| Class of Worker | W |
| Can Read/Write | Yes |
| Mother Tongue | Scotch |
| Birth Country | Scotland |
| Birthplace (normalized) | scotland |
1940
Allegheny-County, Pennsylvania
Head, age 53
Allegheny-County, Pennsylvania · implied b. ~1887 — 4 household members
| Surname | Duffy |
| Given Name | John J. |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 53 |
| Marital Status | Married |
| Birthplace | Scotland |
| 1935 Residence (City) | Pittsburgh |
| 1935 Residence (County) | Allegheny |
| Naturalization Status | Naturalized |
| Occupation | Foreman |
| Industry | Railway |
| Class of Worker | PW |
| Hours Worked | 48 |
| Income (1939) | 2500 |
| Highest Grade | Hs 4 |
| 1935 Residence | Same place |
| Birth Country | Scotland |
| Birthplace (normalized) | scotland |
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 Duffy across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage.
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This person
Anchor record
John Duffy
Head · 1940 · age 53 · b. ~1887 · Pennsylvania
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Confirmed / household (~0.90+)
Probable / derived (~0.65–0.89)
Candidate (<0.65, unverified)
Original Census Page
1940 US Federal Census — Allegheny-County, Pennsylvania
Open full size
1940 US Federal Census — Allegheny-County, Pennsylvania
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-03676-00567)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Bettie L. Means | 21 | Wife | School Teacher | Pennsylvania |
| 2 | Deanne Means | 1 | Daughter | — | Pennsylvania |
| 3 | Helen L. Cook | 20 | Maid | Maid | Pennsylvania |
| 4 | John J. Duffy THIS PERSON | 53 | Head | Foreman | Scotland |
| 5 | Mildred L. Duffy | 44 | Wife | — | Pennsylvania |
| 6 | Helen F. Hart | 26 | Daughter | — | Pennsylvania |
| 7 | William L. Weber | 26 | Lodger | Labor | Pennsylvania |
| 8 | Charles Rhode | 75 | Head | Watchman | Pennsylvania |
| 9 | Thomas A. Jones | 54 | Son in law | Truckman | Pennsylvania |
| 10 | Lucella M. Jones | 53 | Daughter | — | Pennsylvania |
| 11 | Wallace B. Steys | 38 | Head | Auto Mechanic | Pennsylvania |
| 12 | Alvina A. Steys | 32 | Wife | — | Pennsylvania |
| 13 | John A. Steys | 4 | Son | — | Pennsylvania |
| 14 | Frank A. Carr | 52 | Head | Engineer | Pennsylvania |
| 15 | Stella M. Carr | 54 | Wife | — | Pennsylvania |
| 16 | Arthur F. Carr | 23 | Son | Clerk | Pennsylvania |
| 17 | Dorothy R. Carr | 21 | Daughter | Typist | Pennsylvania |
| 18 | Carl J. Euchrig | 51 | Head | Mold Maker | Pennsylvania |
| 19 | Margaret E. Euchrig | 51 | Wife | — | Pennsylvania |
| 20 | Mike Phinelovich | 30 | Head | Recorder | Pennsylvania |
| 21 | Amelia Phinelovich | 28 | Wife | — | Pennsylvania |
| 22 | Dawn Marie Phinelovich | 7 | Daughter | — | Pennsylvania |
| 23 | Yvonne D. Phinelovich | 4 | Daughter | — | Pennsylvania |
| 24 | John Wolejko | 30 | Head | Foreman | Pennsylvania |
| 25 | Olga Wolejko | 25 | Wife | Typist | Pennsylvania |
| 26 | David A. Bridwell | 50 | Head | — | Pennsylvania |
| 27 | Laura E. Bridwell | 50 | Wife | — | Pennsylvania |
| 28 | Ralph B. Mckay | 39 | Head | Draftsman | Pennsylvania |
| 29 | Loretta M. Mckay | 34 | Wife | — | Pennsylvania |
| 30 | Edward N. Mckay | 41 | Lodger | Salesman | Pennsylvania |
| 31 | Margaret E. Mckay | 43 | Lodger | — | Pennsylvania |
| 32 | Oliver B. Douthitt | 43 | Head | Recorder | Pennsylvania |
| 33 | Melba S. Douthitt | 42 | Wife | — | Pennsylvania |
| 34 | Richard B. Douthitt | 16 | Son | — | Pennsylvania |
| 35 | Edward B. Douthitt | 3 | Son | — | Pennsylvania |
| 36 | Block 73 End Of Block 72 | None | — | — | — |
| 37 | Paul C. Greenwald | 25 | Head | Labor | Pennsylvania |
| 38 | Evaline V. Greenwald | 24 | Wife | — | Pennsylvania |
| 39 | Frank Shinkus | 40 | Head | Stationary Engineer | Lithuania |
| 40 | Helen Shinkus | 45 | Wife | — | Lithuania |
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)