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John Mcdonald — 1940 US Census Record
Model Tree available1940 United States Federal Census · Allegheny-County, Pennsylvania
Our Model Tree links this John Mcdonald across the 1920, 1930 and 1940 US Censuses in Allegheny-County, Pennsylvania (XGBoost, ~Confirmed), with identified parents Mary & Mary — first a son (b.~1911), then head of a 3-person household.
Age 29
b. ~1911
Male
Son
Born: West Virginia
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Allegheny-County, Pennsylvania |
| Surname | McDonald |
| Given Name | John J. |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 29 |
| Marital Status | Single |
| Birthplace | West Virginia |
| 1935 Residence (City) | Pittsburgh City |
| 1935 Residence (County) | Allegheny |
| Additional Details | |
| Occupation | Proprietor |
| Industry | Refinery |
| Class of Worker | OA |
| Hours Worked | 60 |
| Income (1939) | 452 |
| Highest Grade | No 8 |
| 1935 Residence | Same House |
| Birth State | West Virginia |
| Birth Country | United States |
| Birthplace (normalized) | west virginia |
| Occupation | Proprietor |
| Township / Ward | Pittsburgh City |
| Est. Birth Year | ~1911 |
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.
3 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to John | Age | Birth yr |
|---|---|---|---|---|
| Katherine Mcdonald | Daughter | — | 33 | ~1907 |
| Mary Mcdonald | Head | — | 72 | ~1868 |
| John Mcdonald | Son | — | 29 | ~1911 |
Census Appearances
1920
Allegheny, Pennsylvania
Son, age 9
Allegheny, Pennsylvania · implied b. ~1911 — 7 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | McDonald |
| Given Name | John |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 9 |
| Marital Status | Single |
| Birthplace | West Virginia |
| Father's Birthplace | Canada |
| Mother's Birthplace | West Virginia |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Birth State | West Virginia |
| Birth Country | United States |
| Birthplace (normalized) | west virginia |
1930
Allegheny, Pennsylvania
Son, age 19
Allegheny, Pennsylvania · implied b. ~1911 — 7 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | McDonald |
| Given Name | John |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 19 |
| Marital Status | Single |
| Birthplace | West Virginia |
| Father's Birthplace | Canada-English |
| Mother's Birthplace | West Virginia |
| Can Read/Write | Yes |
| Veteran | No |
| Birth State | West Virginia |
| Birth Country | United States |
| Birthplace (normalized) | west virginia |
1940
Allegheny-County, Pennsylvania
Son, age 29
Allegheny-County, Pennsylvania · implied b. ~1911 — 3 household members
| Surname | McDonald |
| Given Name | John J. |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 29 |
| Marital Status | Single |
| Birthplace | West Virginia |
| 1935 Residence (City) | Pittsburgh City |
| 1935 Residence (County) | Allegheny |
| Occupation | Proprietor |
| Industry | Refinery |
| Class of Worker | OA |
| Hours Worked | 60 |
| Income (1939) | 452 |
| Highest Grade | No 8 |
| 1935 Residence | Same House |
| Birth State | West Virginia |
| Birth Country | United States |
| Birthplace (normalized) | west virginia |
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 Mcdonald across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage. Identified parents: mother Mary Mcdonald (~0.92 confidence) and mother Mary Mcdonald (~0.92 confidence). The pedigree spans 1 generation with 2 identified ancestors.
Show:
Gen 1
Parents
confidence ≈ 0.92
Mother
Mary Mcdonald
b. ~1868
Source mother
● Household
· direct · ~0.92
Mother
Mary Mcdonald
b. ~1871
Source mother
● Household
· direct · ~0.92
This person
Anchor record
John Mcdonald
Son · 1940 · age 29 · b. ~1911 · Pennsylvania
★ You are viewing this record
Sibling
Katherine Mcdonald
Sibling · 1940 · age 33
Source co-child of head (derived)
● Co-child · derived · ~0.88
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-t0627-03675-00373)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Dolores England | 10 | Grand-daughter | — | Pennsylvania |
| 42 | Robert England | 8 | Grand-son | — | Pennsylvania |
| 43 | John K. Nichol | 50 | Lodger | Salesman | Pennsylvania |
| 44 | Bert Dilley | 31 | Lodger | Metallurgist | Pennsylvania |
| 45 | Robert F. Lewis | 21 | Lodger | Radio Operator | Michigan |
| 46 | James F. Dunn | 35 | Head | Foreman | Pennsylvania |
| 47 | David H. Dunn | 52 | Son | Yardmaster | Pennsylvania |
| 48 | Mary Jones | 63 | Sister-in-law | — | Pennsylvania |
| 49 | Mary E. Mcdonald | 72 | Head | — | West Virginia |
| 50 | Katherine Mcdonald | 33 | Daughter | Teacher | West Virginia |
| 51 | John J. Mcdonald THIS PERSON | 29 | Son | Proprietor | West Virginia |
| 52 | — | None | Here ends Block 35 and Begins Block 37 | — | — |
| 53 | Margaret Schneider | 75 | Head | — | Germany |
| 54 | Joseph Schneider | 46 | Son | — | Pennsylvania |
| 55 | Madeline Mcgann | 44 | Daughter | Clerk | Pennsylvania |
| 56 | Robert Mcgann | 17 | Grandson | — | Pennsylvania |
| 57 | Bernard Mccarthy | 43 | Head | Craneman | Pennsylvania |
| 58 | Alice Mccarthy | 37 | Wife | — | Pennsylvania |
| 59 | Virginia Mccarthy | 19 | Daughter | Stenographer | Pennsylvania |
| 60 | Mary Crickard | 64 | Head | Ladies Lady | Pennsylvania |
| 61 | John Edgecomb | 68 | Head | — | Pennsylvania |
| 62 | Wallace E. Edgecomb | 35 | Son | Lawyer | Pennsylvania |
| 63 | Clara L. Edgecomb | 30 | Daughter | — | Pennsylvania |
| 64 | Michael Crenner | 48 | Head | Meter Reader | Pennsylvania |
| 65 | Edna Crenner | 45 | Wife | — | Pennsylvania |
| 66 | James Crenner | 17 | Son | — | Pennsylvania |
| 67 | Stella Schleick | 51 | Sister-in-law | Domestic | Pennsylvania |
| 68 | Catherine Kreutzer | 62 | Head | — | West Virginia |
| 69 | Barbra Missey | 60 | Head | Janitress | Pennsylvania |
| 70 | Anna Missey | 56 | Sister | Candy Machine Feeder | Pennsylvania |
| 71 | Catherine Sexton | 22 | Niece | Candy Machine Feeder | Pennsylvania |
| 72 | William Sexton | 18 | Nephew | Messenger | Pennsylvania |
| 73 | Paul Sexton | 11 | Nephew | — | Pennsylvania |
| 74 | Clara Allen | 41 | Head | Seamstress | Pennsylvania |
| 75 | James Wesley Parnell | 57 | Lodger | Salesman | Pennsylvania |
| 76 | Howard Sharon | 59 | Head | Laborer | Pennsylvania |
| 77 | Marie Sharon | 51 | Wife | — | Pennsylvania |
| 78 | Howard, Jr. Sharon | 23 | Son | Bartender | Pennsylvania |
| 79 | Mary Waslik | 32 | Niece | Comptometer Operator | Pennsylvania |
| 80 | William Vaught | 30 | Head | Street Car Operator | Pennsylvania |
Pedigree Summary
John + 1 sibling
Gen 1 · 2 parents
~0.92
Max depth 4 (1900–1950 window)
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)