RD
Robert Duncan — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Delaware-County, Pennsylvania
Our Model Tree links this Robert Duncan across the 1930 and 1940 US Censuses in Delaware-County, Pennsylvania (XGBoost, ~Confirmed) — first a son (b.~1925), then head of a 10-person household.
Age 15
b. ~1925
Male
Son
Born: Pennsylvania
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Delaware-County, Pennsylvania |
| Surname | Duncan |
| Given Name | Robert |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 15 |
| Marital Status | Single |
| Birthplace | Pennsylvania |
| 1935 Residence (City) | Tinicum Township |
| 1935 Residence (County) | Delaware |
| Additional Details | |
| Highest Grade | No 2 |
| 1935 Residence | Same house |
| Birth State | Pennsylvania |
| Birth Country | United States |
| Birthplace (normalized) | pennsylvania |
| Township / Ward | Tinicum Township |
| Est. Birth Year | ~1925 |
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.
10 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to Robert | Age | Birth yr |
|---|---|---|---|---|
| John Duncan | Son | — | 8 | ~1932 |
| William Duncan | Head | — | 55 | ~1885 |
| Joseph Duncan | Son | — | 13 | ~1927 |
| Clara Duncan | Daughter | — | 5 | ~1935 |
| Robert Duncan | Son | — | 15 | ~1925 |
| William Duncan | Son | — | 18 | ~1922 |
| Arthur Duncan | Son | — | 11 | ~1929 |
| Dorothy Duncan | Daughter | — | 10 | ~1930 |
| Ida Duncan | Spouse | — | 40 | ~1900 |
| Albert Duncan | Son | — | 17 | ~1923 |
Census Appearances
1930
Delaware, Pennsylvania
Son, age 5
Delaware, Pennsylvania · implied b. ~1925 — 10 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Duncan |
| Given Name | Robert |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 5 |
| Marital Status | Single |
| Birthplace | Pennsylvania |
| Father's Birthplace | Pennsylvania |
| Mother's Birthplace | Poland |
| Birth State | Pennsylvania |
| Birth Country | United States |
| Birthplace (normalized) | pennsylvania |
1940
Delaware-County, Pennsylvania
Son, age 15
Delaware-County, Pennsylvania · implied b. ~1925 — 10 household members
| Surname | Duncan |
| Given Name | Robert |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 15 |
| Marital Status | Single |
| Birthplace | Pennsylvania |
| 1935 Residence (City) | Tinicum Township |
| 1935 Residence (County) | Delaware |
| Highest Grade | No 2 |
| 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 Robert Duncan across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
Robert Duncan
Son · 1940 · age 15 · b. ~1925 · Pennsylvania
★ You are viewing this record
Sibling
William Duncan
Sibling · 1940 · age 18
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
John Duncan
Sibling · 1940 · age 8
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Joseph Duncan
Sibling · 1940 · age 13
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Clara Duncan
Sibling · 1940 · age 5
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Arthur Duncan
Sibling · 1940 · age 11
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Albert Duncan
Sibling · 1940 · age 17
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Dorothy Duncan
Sibling · 1940 · age 10
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 — Delaware-County, Pennsylvania
Open full size
1940 US Federal Census — Delaware-County, Pennsylvania
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-03496-00559)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Jean Betham | 7 | Daughter | — | Pennsylvania |
| 2 | Edward Chamberlin | 57 | Head | Draftsman | Pennsylvania |
| 3 | Rebecca Chamberlin | 76 | Mother | — | Pennsylvania |
| 4 | Magdeline Brittner | 71 | Head | — | Pennsylvania |
| 5 | Kathryn Kepler | 60 | Head | — | Pennsylvania |
| 6 | Charles Kepler | 23 | Son | Cabinet Maker | Pennsylvania |
| 7 | Joseph Kepler | 21 | Son | Laborer | Pennsylvania |
| 8 | William Mcgovern | 73 | Head | — | Pennsylvania |
| 9 | Almira Mcgovern | 76 | Wife | — | Pennsylvania |
| 10 | Joseph Sr. Kepler | 77 | Head | — | Pennsylvania |
| 11 | William H. Duncan | 55 | Head | Blade Grinder | Pennsylvania |
| 12 | Ida Duncan | 40 | Wife | — | Poland |
| 13 | William Jr. Duncan | 18 | Son | — | Pennsylvania |
| 14 | Albert Duncan | 17 | Son | — | Pennsylvania |
| 15 | Robert Duncan THIS PERSON | 15 | Son | — | Pennsylvania |
| 16 | Joseph Duncan | 13 | Son | — | Pennsylvania |
| 17 | Arthur Duncan | 11 | Son | — | Pennsylvania |
| 18 | Dorothy Duncan | 10 | Daughter | — | Pennsylvania |
| 19 | John Duncan | 8 | Son | — | Pennsylvania |
| 20 | Clara Duncan | 5 | Daughter | — | Pennsylvania |
| 21 | James B. Burnes | 63 | Head | Watchman | Pennsylvania |
| 22 | Ada Burnes | 52 | Wife | — | Virginia |
| 23 | Alexandric Pocurec | 64 | Head | — | Lithuania |
| 24 | Josephine Pocurec | 25 | Daughter | — | Pennsylvania |
| 25 | Joseph Sax | 52 | Head | Machine Operator | Pennsylvania |
| 26 | Edith Sax | 52 | Wife | — | New York |
| 27 | Michael Stefancki | 36 | Head | Machine Operator | Pennsylvania |
| 28 | Joseph Slazydrich | 55 | Head | Laborer | Lithuania |
| 29 | Helen Slazydrich | 47 | Wife | — | Lithuania |
| 30 | William Sr. Ketchen | 30 | Head | Truck Driver | Pennsylvania |
| 31 | Irene Ketchen | 24 | Wife | — | Pennsylvania |
| 32 | William Jr. Ketchen | 4 | Son | — | Pennsylvania |
| 33 | David Ketchen | 1 | Son | — | Pennsylvania |
| 34 | George Proski | 74 | Head | — | Czechoslovakia |
| 35 | Annie Proski | 68 | Wife | — | Russia |
| 36 | William Jr. Lang | 31 | Head | Assembler | Pennsylvania |
| 37 | Marie Lang | 29 | Wife | — | Pennsylvania |
| 38 | William Jr. Lang | 2 | Son | — | Pennsylvania |
| 39 | Irene Simons | 27 | Sister-in-law | Inspector | Pennsylvania |
| 40 | Mary Simpson | 22 | Niece | Shader | Pennsylvania |
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)