JD
James Duffy — 1940 US Census Record
Model Tree available1940 United States Federal Census · Allegheny-County, Pennsylvania
Our Model Tree links this James Duffy across the 1920, 1930 and 1940 US Censuses in Allegheny-County, Pennsylvania (XGBoost, ~Confirmed), with identified parents Edward & Mary — first a son (b.~1915), then head of a 3-person household.
Age 25
b. ~1915
Male
Son
Born: Pennsylvania
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Allegheny-County, Pennsylvania |
| Surname | Duffy |
| Given Name | James |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 25 |
| Marital Status | Single |
| Birthplace | Pennsylvania |
| 1935 Residence (City) | Pittsburgh |
| 1935 Residence (County) | Allegheny |
| Additional Details | |
| Occupation | repairs elevators |
| Industry | office building |
| Class of Worker | PW |
| Hours Worked | 26 |
| Income (1939) | 650 |
| Highest Grade | H-4 |
| 1935 Residence | Same house |
| Birth State | Pennsylvania |
| Birth Country | United States |
| Birthplace (normalized) | pennsylvania |
| Occupation | Repairs Elevators |
| Township / Ward | Pittsburgh |
| Est. Birth Year | ~1915 |
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 James | Age | Birth yr |
|---|---|---|---|---|
| Mary Duffy | Head | — | 50 | ~1890 |
| James Duffy | Son | — | 25 | ~1915 |
| John Duffy | Son | — | 23 | ~1917 |
Census Appearances
1920
Allegheny, Pennsylvania
Son, age 4
Allegheny, Pennsylvania · implied b. ~1916 — 5 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Duffy |
| Given Name | James |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 4 |
| Marital Status | Single |
| Birthplace | Pennsylvania |
| Father's Birthplace | Pennsylvania |
| Mother's Birthplace | Pennsylvania |
| Can Read | No |
| Can Write | No |
| Birth State | Pennsylvania |
| Birth Country | United States |
| Birthplace (normalized) | pennsylvania |
1930
Allegheny, Pennsylvania
Son, age 14
Allegheny, Pennsylvania · implied b. ~1916 — 5 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Duffy |
| Given Name | James |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 14 |
| Marital Status | Single |
| Birthplace | Pennsylvania |
| Father's Birthplace | Pennsylvania |
| Mother's Birthplace | Pennsylvania |
| Can Read/Write | Yes |
| Birth State | Pennsylvania |
| Birth Country | United States |
| Birthplace (normalized) | pennsylvania |
1940
Allegheny-County, Pennsylvania
Son, age 25
Allegheny-County, Pennsylvania · implied b. ~1915 — 3 household members
| Surname | Duffy |
| Given Name | James |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 25 |
| Marital Status | Single |
| Birthplace | Pennsylvania |
| 1935 Residence (City) | Pittsburgh |
| 1935 Residence (County) | Allegheny |
| Occupation | repairs elevators |
| Industry | office building |
| Class of Worker | PW |
| Hours Worked | 26 |
| Income (1939) | 650 |
| Highest Grade | H-4 |
| 1935 Residence | Same house |
| Birth State | Pennsylvania |
| Birth Country | United States |
| Birthplace (normalized) | pennsylvania |
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 James Duffy across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage. Identified parents: father Edward Duffy (~0.92 confidence) and mother Mary Duffy (~0.92 confidence) and mother Mary Duffy (~0.92 confidence) and mother Mary Duffy (~0.92 confidence). The pedigree spans 1 generation with 4 identified ancestors.
Show:
Gen 1
Parents
confidence ≈ 0.92
Father
Edward Duffy
b. ~1884
Source father
● Household
· direct · ~0.92
Mother
Mary Duffy
b. ~1889
Source mother
● Household
· direct · ~0.92
Mother
Mary Duffy
b. ~1889
Source mother
● Household
· direct · ~0.92
Mother
Mary Duffy
b. ~1890
Source mother
● Household
· direct · ~0.92
This person
Anchor record
James Duffy
Son · 1940 · age 25 · b. ~1915 · Pennsylvania
★ You are viewing this record
Sibling
John Duffy
Sibling · 1940 · age 23
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-t0627-03672-00614)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Mary J. Long | 74 | Head | — | Pennsylvania |
| 42 | John H. Gelpheiser | 56 | Head | Cooper | Pennsylvania |
| 43 | Celia Gelpheiser | 64 | Wife | — | Pennsylvania |
| 44 | Margaret Nagy | 71 | Head | — | Hungary |
| 45 | George Varady | 69 | Lodger | — | Hungary |
| 46 | James J. Blount | 47 | Head | Laborer | Pennsylvania |
| 47 | Lillian Blount | 44 | Wife | — | Pennsylvania |
| 48 | Armando Solli | 25 | Head | Laborer | Pennsylvania |
| 49 | Rose Solli | 25 | Wife | — | Pennsylvania |
| 50 | Joseph Solli | 3 | Son | — | Pennsylvania |
| 51 | John Solli | 0 | Son | — | Pennsylvania |
| 52 | John Mcgrath | 29 | Head | Roofer | Pennsylvania |
| 53 | Mildred Mcgrath | 28 | Wife | — | Pennsylvania |
| 54 | John Jr. Mcgrath | 4 | Son | — | Pennsylvania |
| 55 | Mildred Mcgrath | 2 | Daughter | — | Pennsylvania |
| 56 | Nickol Michalizyn | 54 | Head | Laborer | Hungary |
| 57 | Russell Deer | 36 | Head | Milk Man | Pennsylvania |
| 58 | Elizabeth Deer | 44 | Wife | — | Pennsylvania |
| 59 | Ida Deer | 14 | Daughter | — | Pennsylvania |
| 60 | Russell W. Deer | 12 | Son | — | Pennsylvania |
| 61 | Lois Deer | 10 | Daughter | — | Pennsylvania |
| 62 | Betty Deer | 4 | Daughter | — | Pennsylvania |
| 63 | Adam Meravi | 59 | Head | Laborer | Austria |
| 64 | George Barla | 67 | Lodger | — | Austria |
| 65 | Mary H. Duffy | 50 | Head | — | Pennsylvania |
| 66 | James Duffy THIS PERSON | 25 | Son | Repairs Elevators | Pennsylvania |
| 67 | John P. Duffy | 23 | Son | Hatter | Pennsylvania |
| 68 | Joseph Novak | 24 | Head | Laborer | Pennsylvania |
| 69 | Marion Novak | 24 | Wife | — | Pennsylvania |
| 70 | Betty Ann Novak | 9 | Daughter | — | Pennsylvania |
| 71 | Elaine Novak | 4 | Daughter | — | Pennsylvania |
| 72 | Joseph Jr. Novak | 3 | Son | — | Pennsylvania |
| 73 | Harry Newman | 53 | Head | Laborer | Pennsylvania |
| 74 | Wesley Newman | 52 | Brother | Truck Driver | Pennsylvania |
| 75 | Birdie Newman | 48 | Sister | — | Pennsylvania |
| 76 | Sarah Newman | 82 | Mother | — | Pennsylvania |
| 77 | Charles H. Suar | 25 | Head | Dipper | Pennsylvania |
| 78 | Rose Suar | 22 | Wife | — | Pennsylvania |
| 79 | Rosemary Suar | 1 | Daughter | — | Pennsylvania |
| 80 | Rosa Winkler | 48 | Head | Matron | Austria |
Pedigree Summary
James + 1 sibling
Gen 1 · 4 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)