JD
John Duncan — 1940 US Census Record
Model Tree available1940 United States Federal Census · Suffolk-County, Massachusetts
Our Model Tree links this John Duncan across the 1920, 1930 and 1940 US Censuses in Suffolk-County, Massachusetts (XGBoost, ~Confirmed), with identified parents Charles & Rosetta — first a son (b.~1911), then head of a 5-person household.
Age 29
b. ~1911
Male
Son
Born: Massachusetts
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Suffolk-County, Massachusetts |
| Surname | Duncan |
| Given Name | John H. |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 29 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| 1935 Residence (City) | Boston |
| 1935 Residence (County) | Suffolk |
| Additional Details | |
| Occupation | Chauffeur |
| Industry | General Trucking |
| Class of Worker | PW |
| Hours Worked | 48 |
| Income (1939) | 1200 |
| Highest Grade | H-4 |
| 1935 Residence | Same House |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
| Occupation | Chauffeur |
| Township / Ward | Boston |
| 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.
5 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to John | Age | Birth yr |
|---|---|---|---|---|
| Mabel Duncan | Daughter | — | 23 | ~1917 |
| Rosella Duncan | Head | — | 57 | ~1883 |
| John Duncan | Son | — | 29 | ~1911 |
| Charles Duncan | Son | — | 21 | ~1919 |
| William Duncan | Son | — | 21 | ~1919 |
Census Appearances
1920
Suffolk, Massachusetts
Son, age 9
Suffolk, Massachusetts · implied b. ~1911 — 9 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Duncan |
| Given Name | John H. |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 9 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| Father's Birthplace | New York |
| Mother's Birthplace | Massachusetts |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
1930
Suffolk, Massachusetts
Son, age 19
Suffolk, Massachusetts · implied b. ~1911 — 7 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Duncan |
| Given Name | John Henry |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 19 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| Father's Birthplace | New York |
| Mother's Birthplace | Massachusetts |
| Occupation | Stenographer |
| Industry | Paper Co |
| Class of Worker | W |
| Can Read/Write | Yes |
| Veteran | No |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
1940
Suffolk-County, Massachusetts
Son, age 29
Suffolk-County, Massachusetts · implied b. ~1911 — 5 household members
| Surname | Duncan |
| Given Name | John H. |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 29 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| 1935 Residence (City) | Boston |
| 1935 Residence (County) | Suffolk |
| Occupation | Chauffeur |
| Industry | General Trucking |
| Class of Worker | PW |
| Hours Worked | 48 |
| Income (1939) | 1200 |
| Highest Grade | H-4 |
| 1935 Residence | Same House |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
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 Duncan across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage. Identified parents: father Charles Duncan (~0.92 confidence) and mother Rosetta Duncan (~0.92 confidence) and mother Ella Duncan (~0.92 confidence). The pedigree spans 1 generation with 3 identified ancestors.
Show:
Gen 1
Parents
confidence ≈ 0.92
Father
Charles Duncan
b. ~1880
Source father
● Household
· direct · ~0.92
Mother
Rosetta Duncan
b. ~1883
Source mother
● Household
· direct · ~0.92
Mother
Ella Duncan
b. ~1884
Source mother
● Household
· direct · ~0.92
This person
Anchor record
John Duncan
Son · 1940 · age 29 · b. ~1911 · Massachusetts
★ You are viewing this record
Sibling
Charles Duncan
Sibling · 1940 · age 21
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Mabel Duncan
Sibling · 1940 · age 23
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
William Duncan
Sibling · 1940 · age 21
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 — Suffolk-County, Massachusetts
Open full size
1940 US Federal Census — Suffolk-County, Massachusetts
Page Contents
39 people indexed on this census page (nara:1940:m-t0627-01666-00413)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Frank J. Wisco | 38 | Head | Proprietor | Massachusetts |
| 42 | Anne M. Wisco | 31 | Wife | Proprietor | Massachusetts |
| 43 | Eugene P. Stone | 12 | Son | — | Massachusetts |
| 44 | James Mullen | 45 | Head | Watchman | Eire |
| 45 | Catherine Mullen | 40 | Wife | — | Eire |
| 46 | Joseph Daley | 21 | Step-son | Draftsman | Massachusetts |
| 47 | Catherine Daley | 14 | Step-daughter | — | Massachusetts |
| 48 | James Mullen | 7 | Son | — | Massachusetts |
| 49 | John Mullen | 4 | Son | — | Massachusetts |
| 50 | Addison P. Beardsley | 66 | Head | Teacher | Canada-Eng |
| 51 | Henrietta A. Beardsley | 62 | Wife | Social Service | Canada-Eng |
| 52 | Martin H. Keogh | 55 | Head | Printer | Massachusetts |
| 53 | Mary A. Keogh | 55 | Wife | — | Massachusetts |
| 54 | Joseph L. Keogh | 27 | Son | Supervisor | Massachusetts |
| 55 | Eleanor Keogh | 19 | Daughter | Cashier | Massachusetts |
| 56 | Eileen Keogh | 18 | Daughter | — | Massachusetts |
| 57 | Edward E. Devoto | 42 | Head | — | Massachusetts |
| 58 | Louis B. Devoto | 59 | Brother | Customs Inspector | Massachusetts |
| 59 | Maude H. Binney | 71 | Head | — | Massachusetts |
| 60 | Daisy J. Houghton | 74 | Companion | Companion | Massachusetts |
| 61 | Patrick J. Melody | 48 | Head | Commissioner | Eire |
| 62 | Mary Melody | 46 | Wife | — | Massachusetts |
| 63 | Eleanor Melody | 17 | Daughter | — | Massachusetts |
| 64 | Marguerite Melody | 15 | Daughter | — | Massachusetts |
| 65 | Rose Melody | 14 | Daughter | — | Massachusetts |
| 66 | Paul Melody | 12 | Son | — | Massachusetts |
| 67 | Rosella Duncan | 57 | Head | — | Massachusetts |
| 68 | Mabel M. Duncan | 23 | Daughter | Saleslady | Massachusetts |
| 69 | John H. Duncan THIS PERSON | 29 | Son | Chauffeur | Massachusetts |
| 70 | William Duncan | 21 | Son | Helper | Massachusetts |
| 71 | Charles A. Duncan | 21 | Son | Typist | Massachusetts |
| 72 | Frank S. Fillmore | 39 | Head | Salesman | Canada-Eng |
| 73 | Eva S. Fillmore | 36 | Wife | — | Canada-Eng |
| 74 | Roderick S. Fillmore | 16 | Son | — | Canada-Eng |
| 75 | Allan H. Fillmore | 10 | Son | — | Massachusetts |
| 76 | Margaret T. Murphy | 63 | Head | — | Massachusetts |
| 77 | Frances Murphy | 28 | Daughter | High School Teacher | Massachusetts |
| 78 | James C. Murphy | 26 | Son | Agent | Massachusetts |
| 79 | William Murphy | 24 | Son | Truck Driver Helper | Massachusetts |
Pedigree Summary
John + 3 siblings
Gen 1 · 3 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)