MD
Mary Duncan — 1940 US Census Record
Model Tree available1940 United States Federal Census · Indiana-County, Pennsylvania
Our Model Tree links this Mary Duncan across the 1920, 1930 and 1940 US Censuses in Indiana-County, Pennsylvania (XGBoost, ~Confirmed), with identified parents Carrie & C — first a daughter (b.~1910), then head of a 4-person household.
Age 30
b. ~1910
Female
Daughter
Born: Pennsylvania
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Indiana-County, Pennsylvania |
| Surname | Duncan |
| Given Name | Mary C. |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 30 |
| Marital Status | Single |
| Birthplace | Pennsylvania |
| 1935 Residence (City) | Borough |
| 1935 Residence (County) | Indiana |
| Additional Details | |
| Occupation | Clerk |
| Industry | County Office |
| Class of Worker | GW |
| Hours Worked | 40 |
| Income (1939) | 600 |
| Highest Grade | C 4 |
| 1935 Residence | Same place |
| Birth State | Pennsylvania |
| Birth Country | United States |
| Birthplace (normalized) | pennsylvania |
| Occupation | Clerk |
| Township / Ward | Borough |
| Est. Birth Year | ~1910 |
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 Mary | Age | Birth yr |
|---|---|---|---|---|
| Mary Duncan | Daughter | — | 30 | ~1910 |
| C Duncan | Head | — | 61 | ~1879 |
| Annie Kline | Other | — | 90 | ~1850 |
| Carrie Duncan | Spouse | — | 64 | ~1876 |
Census Appearances
1920
Indiana, Pennsylvania
Daughter, age 9
Indiana, Pennsylvania · implied b. ~1911 — 4 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Duncan |
| Given Name | Mary D. |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 9 |
| Marital Status | Single |
| Birthplace | Pennsylvania |
| Father's Birthplace | Pennsylvania |
| Mother's Birthplace | Pennsylvania |
| Occupation | none |
| Speaks English | Yes |
| Birth State | Pennsylvania |
| Birth Country | United States |
| Birthplace (normalized) | pennsylvania |
1930
Indiana, Pennsylvania
Daughter, age 20
Indiana, Pennsylvania · implied b. ~1910 — 5 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Duncan |
| Given Name | Mary G |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 20 |
| Marital Status | Single |
| Birthplace | Pennsylvania |
| Father's Birthplace | Pennsylvania |
| Mother's Birthplace | Pennsylvania |
| Can Read/Write | Yes |
| Home Owned/Rented | No |
| Birth State | Pennsylvania |
| Birth Country | United States |
| Birthplace (normalized) | pennsylvania |
1940
Indiana-County, Pennsylvania
Daughter, age 30
Indiana-County, Pennsylvania · implied b. ~1910 — 4 household members
| Surname | Duncan |
| Given Name | Mary C. |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 30 |
| Marital Status | Single |
| Birthplace | Pennsylvania |
| 1935 Residence (City) | Borough |
| 1935 Residence (County) | Indiana |
| Occupation | Clerk |
| Industry | County Office |
| Class of Worker | GW |
| Hours Worked | 40 |
| Income (1939) | 600 |
| Highest Grade | C 4 |
| 1935 Residence | Same place |
| 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 Mary Duncan across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage. Identified parents: mother Carrie Duncan (~0.92 confidence) and father C Duncan (~0.92 confidence) and father Charles Duncan (~0.92 confidence). The pedigree spans 1 generation with 3 identified ancestors.
Show:
Gen 1
Parents
confidence ≈ 0.92
Mother
Carrie Duncan
b. ~1877
Source mother
● Household
· direct · ~0.92
Father
C Duncan
b. ~1879
Source father
● Household
· direct · ~0.92
Father
Charles Duncan
b. ~1879
Source father
● Household
· direct · ~0.92
This person
Anchor record
Mary Duncan
Daughter · 1940 · age 30 · b. ~1910 · Pennsylvania
★ You are viewing this record
Confirmed / household (~0.90+)
Probable / derived (~0.65–0.89)
Candidate (<0.65, unverified)
Original Census Page
1940 US Federal Census — Indiana-County, Pennsylvania
Open full size
1940 US Federal Census — Indiana-County, Pennsylvania
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-03518-00117)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | C. W. Duncan | 61 | Head | Postmaster | Pennsylvania |
| 42 | Carrie Duncan | 64 | Wife | — | Pennsylvania |
| 43 | Mary C. Duncan THIS PERSON | 30 | Daughter | Clerk | Pennsylvania |
| 44 | Annie Kline | 90 | Boarder | — | New York |
| 45 | Jay Glassford | 45 | Head | Clerk | Pennsylvania |
| 46 | Linn R. Glassford | 44 | Wife | Dealer | Pennsylvania |
| 47 | Sadie E. Glassford | 76 | Wife | — | Pennsylvania |
| 48 | John Glassford | 40 | Son | Dealer | Pennsylvania |
| 49 | Mary Harvey | 20 | Maid | Maid | Pennsylvania |
| 50 | Samuel Rinn | 48 | Head | Proprietor | Pennsylvania |
| 51 | Nell Rinn | 46 | Wife | — | Pennsylvania |
| 52 | Virginia Rinn | 16 | Daughter | — | Pennsylvania |
| 53 | Samuel Jr. Rinn | 12 | Son | — | Pennsylvania |
| 54 | Elizabeth Kylin | 31 | Maid | Maid | Pennsylvania |
| 55 | Logan Bence | 56 | Head | Manager | Pennsylvania |
| 56 | Sarah Bence | 57 | Wife | — | Pennsylvania |
| 57 | Agnes Bence | 19 | Daughter | — | Pennsylvania |
| 58 | Logan Bence | 14 | Son | — | Pennsylvania |
| 59 | Eugene Bence | 12 | Son | — | Pennsylvania |
| 60 | Charles Garvin | 60 | Head | — | Pennsylvania |
| 61 | Don S. Detery | 52 | Son-in-law | Court Crier | Pennsylvania |
| 62 | Grace G. Detery | 44 | Daughter | — | Ohio |
| 63 | George Little | 69 | Head | Clerk | Pennsylvania |
| 64 | Minnie Little | 68 | Wife | — | Pennsylvania |
| 65 | Blanche Little | 40 | Daughter | — | Pennsylvania |
| 66 | Clara Bell Pardee | 10 | Niece | — | Pennsylvania |
| 67 | Harry B. Mcneil | 49 | Head | Broker | Pennsylvania |
| 68 | Doris A. Mcneil | 48 | Wife | — | Pennsylvania |
| 69 | Robert L. Mcneil | 19 | Son | Laborer | Pennsylvania |
| 70 | Jack H. Mcneil | 14 | Son | — | Pennsylvania |
| 71 | Walter H. Frank | 62 | Head | Investigator | Maryland |
| 72 | Jessie Frank | 77 | Wife | — | Pennsylvania |
| 73 | Jack Davis | 36 | Head | Owner | New York |
| 74 | Vera Davis | 36 | Wife | — | Russia |
| 75 | Philip Davis | 1 | Son | — | Pennsylvania |
| 76 | Floyd Healer | 33 | Head | Salesman | Pennsylvania |
| 77 | Zoe Adelaide Healer | 22 | Wife | — | Pennsylvania |
| 78 | John Floyd Healer | 3 | Son | — | Pennsylvania |
| 79 | Richard Healer | 22 | Brother | Clerk | Pennsylvania |
| 80 | A. P. Anderson | 45 | Head | Merchant | Pennsylvania |
Pedigree Summary
Mary
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)