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John Slater — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Cook-County, Illinois
Our Model Tree links this John Slater across the 1930 and 1940 US Censuses in Cook-County, Illinois (XGBoost, ~Confirmed) — first a son (b.~1925), then head of a 9-person household.
Age 15
b. ~1925
Male
Son
Born: Illinois
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Cook-County, Illinois |
| Surname | Slater |
| Given Name | John |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 15 |
| Marital Status | Single |
| Birthplace | Illinois |
| 1935 Residence (City) | Chicago City |
| 1935 Residence (County) | Cook |
| Additional Details | |
| Industry | 0 |
| Highest Grade | G 9 |
| 1935 Residence | Same place |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
| Township / Ward | Chicago City |
| 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.
9 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to John | Age | Birth yr |
|---|---|---|---|---|
| Joseph Slater | Son | — | 8 | ~1932 |
| John Vucsko | Other | — | 18 | ~1922 |
| Cornelius Slater | Son | — | 19 | ~1921 |
| Cornelius Slater | Head | — | 44 | ~1896 |
| Anna Slater | Spouse | — | 41 | ~1899 |
| Mary Slater | Daughter | — | 12 | ~1928 |
| Lillian Slater | Daughter | — | 21 | ~1919 |
| Alice Slater | Daughter | — | 4 | ~1936 |
| John Slater | Son | — | 15 | ~1925 |
Census Appearances
1930
Cook, Illinois
Son, age 6
Cook, Illinois · implied b. ~1924 — 4 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Slater |
| Given Name | John |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 6 |
| Marital Status | Single |
| Birthplace | Illinois |
| Father's Birthplace | Indiana |
| Mother's Birthplace | Iowa |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1940
Cook-County, Illinois
Son, age 15
Cook-County, Illinois · implied b. ~1925 — 9 household members
| Surname | Slater |
| Given Name | John |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 15 |
| Marital Status | Single |
| Birthplace | Illinois |
| 1935 Residence (City) | Chicago City |
| 1935 Residence (County) | Cook |
| Industry | 0 |
| Highest Grade | G 9 |
| 1935 Residence | Same place |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
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 Slater across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
John Slater
Son · 1940 · age 15 · b. ~1925 · Illinois
★ You are viewing this record
Sibling
Mary Slater
Sibling · 1940 · age 12
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Joseph Slater
Sibling · 1940 · age 8
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Cornelius Slater
Sibling · 1940 · age 19
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Lillian Slater
Sibling · 1940 · age 21
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Alice Slater
Sibling · 1940 · age 4
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 — Cook-County, Illinois
Open full size
1940 US Federal Census — Cook-County, Illinois
Page Contents
39 people indexed on this census page (nara:1940:m-t0627-00939-01011)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Glenn Hunt | 45 | Cousin | Mechanic | Kansas |
| 2 | David P. Cook | 42 | Lodger | Policeman | Illinois |
| 3 | John Simms | 40 | Head | Fireman | Ohio |
| 4 | Lucille Simms | 40 | Wife | — | Illinois |
| 5 | Marilyn Simms | 12 | Daughter | — | Illinois |
| 6 | Otto J. Ludwig | 67 | Head | — | Germany |
| 7 | Evelyn Schmitt | 30 | Daughter | Secretary | Illinois |
| 8 | Amelia Adubas | 59 | Head | — | Lithuania |
| 9 | Sam Jakubas | 59 | Lodger | Barber | Italy |
| 10 | Adam Rucus | 48 | Lodger | Repair Man | Lithuania |
| 11 | James Marcinkus | 45 | Head | Carpenter | Lithuania |
| 12 | Rose Marcinkus | 39 | Wife | — | Lithuania |
| 13 | Alex Topolski | 25 | Son | Welder | Illinois |
| 14 | James Bildziukewicz | 44 | Lodger | Carpenter | Lithuania |
| 15 | John Carroll | 23 | Head | Classified Laborer | Illinois |
| 16 | Eileen Carroll | 21 | Wife | Cashier | Illinois |
| 17 | Clare Carroll | 46 | Mother | Starcher | Illinois |
| 18 | Frieda De Bell | 47 | Aunt | Sorter | Germany |
| 19 | Marie Murphy | 34 | Head | Sr. Typist | Illinois |
| 20 | Donald Murphy | 11 | Son | — | Illinois |
| 21 | Robert Murphy | 10 | Son | — | Illinois |
| 22 | Frank Krieg | 65 | Lodger | — | Illinois |
| 23 | Melvin Winters | 23 | Lodger | Laborer | Illinois |
| 24 | Cornelius Slater | 44 | Head | Locomotive Engineer | Germany |
| 25 | Anna Slater | 41 | Wife | — | Germany |
| 26 | Lillian Slater | 21 | Daughter | Stenographer | Illinois |
| 27 | Cornelius Jr. Slater | 19 | Son | Locomotive Fireman | Illinois |
| 28 | John Slater THIS PERSON | 15 | Son | — | Illinois |
| 29 | Mary Ann Slater | 12 | Daughter | — | Illinois |
| 30 | Joseph Slater | 8 | Son | — | Illinois |
| 31 | Alice D. Slater | 4 | Daughter | — | Illinois |
| 32 | John Vucsko | 18 | Nephew | Machine Hand | Illinois |
| 33 | Alex Stankiewicz | 62 | Head | Tailor | Poland |
| 34 | Mary E. Stankiewicz | 58 | Wife | — | England |
| 35 | Elizabeth Stankiewicz | 27 | Daughter | Secretary | England |
| 36 | John Stankiewicz | 18 | Son | New Worker | Illinois |
| 37 | Orville Vincent | 50 | Head | Salesman | Illinois |
| 38 | Helen Vincent | 39 | Wife | — | Illinois |
| 39 | Betty Vincent | 21 | Daughter | Filing Clerk | Illinois |
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)