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John Decker — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Cook-County, Illinois
Our Model Tree links this John Decker across the 1930 and 1940 US Censuses in Cook-County, Illinois (XGBoost, ~Confirmed) — first a son (b.~1923), then head of a 8-person household.
Age 17
b. ~1923
Male
Son
Born: Illinois
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Cook-County, Illinois |
| Surname | Decker |
| Given Name | John |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 17 |
| Marital Status | Single |
| Birthplace | Illinois |
| 1935 Residence (City) | Evanston City |
| 1935 Residence (County) | Cook |
| Additional Details | |
| Occupation | Delivery boy |
| Industry | Retail dry goods |
| Class of Worker | PW |
| Hours Worked | 48 |
| Income (1939) | 0 |
| Highest Grade | No 8 |
| 1935 Residence | Same house |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
| Occupation | Delivery Boy |
| Township / Ward | Evanston City |
| Est. Birth Year | ~1923 |
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.
8 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to John | Age | Birth yr |
|---|---|---|---|---|
| Elizabeth Decker | Spouse | — | 41 | ~1899 |
| Betty Decker | Daughter | — | 5 | ~1935 |
| John Decker | Son | — | 17 | ~1923 |
| John Decker | Head | — | 41 | ~1899 |
| Ruth Decker | Daughter | — | 13 | ~1927 |
| Shirley Decker | Daughter | — | 10 | ~1930 |
| Cornelius Decker | Other | — | 53 | ~1887 |
| Anna Decker | Daughter | — | 15 | ~1925 |
Census Appearances
1930
Cook, Illinois
Son, age 6
Cook, Illinois · implied b. ~1924 — 6 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Decker |
| Given Name | John |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 6 |
| Marital Status | Single |
| Birthplace | Illinois |
| Father's Birthplace | Ohio |
| Mother's Birthplace | Illinois |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1940
Cook-County, Illinois
Son, age 17
Cook-County, Illinois · implied b. ~1923 — 8 household members
| Surname | Decker |
| Given Name | John |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 17 |
| Marital Status | Single |
| Birthplace | Illinois |
| 1935 Residence (City) | Evanston City |
| 1935 Residence (County) | Cook |
| Occupation | Delivery boy |
| Industry | Retail dry goods |
| Class of Worker | PW |
| Hours Worked | 48 |
| Income (1939) | 0 |
| Highest Grade | No 8 |
| 1935 Residence | Same house |
| 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 Decker across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
John Decker
Son · 1940 · age 17 · b. ~1923 · Illinois
★ You are viewing this record
Sibling
Shirley Decker
Sibling · 1940 · age 10
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Anna Decker
Sibling · 1940 · age 15
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Betty Decker
Sibling · 1940 · age 5
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Ruth Decker
Sibling · 1940 · age 13
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
40 people indexed on this census page (nara:1940:m-t0627-00779-00076)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Ethel Foster | 30 | Lodger | Servant | South Carolina |
| 2 | Herbert Foster | 31 | Lodger | — | Illinois |
| 3 | Charity White | 53 | Lodger | Servant | South Carolina |
| 4 | Joseph Love | 44 | Lodger | Service Man | Georgia |
| 5 | Cora Nettles | 45 | Housekeeper | Housekeeper | Indiana |
| 6 | Richard Frazier | 45 | Head | Laborer | South Carolina |
| 7 | Frazier Frazier | 45 | Wife | — | South Carolina |
| 8 | Claudia Mae Frazier | 21 | Daughter | Servant | South Carolina |
| 9 | Henry Frazier | 20 | Son | Delivery Boy | South Carolina |
| 10 | Margie Frazier | 18 | Daughter | Servant | South Carolina |
| 11 | Thelma Frazier | 11 | Daughter | — | Illinois |
| 12 | Alvenia Frazier | 6 | Daughter | — | Illinois |
| 13 | Joan R. Lewis | 3 | Daughter | — | Illinois |
| 14 | Harry E. Johnson | 71 | Head | Clergyman | Kentucky |
| 15 | Mary E. Johnson | 58 | Wife | — | Ohio |
| 16 | Audrey Brown | 38 | Head | Servant | South Carolina |
| 17 | Ruby Brown | 15 | Daughter | — | South Carolina |
| 18 | Charlotte Brown | 11 | Daughter | — | Illinois |
| 19 | Jesse Brown | 10 | Son | — | Illinois |
| 20 | John Barre | 36 | Head | Truck Driver | Illinois |
| 21 | Anne Barre | 33 | Wife | — | Illinois |
| 22 | Raymond Barre | 12 | Son | — | Illinois |
| 23 | Russell Barre | 2 | Son | — | Illinois |
| 24 | George Heldak | 27 | Head | Head Of Stock | Illinois |
| 25 | Edna Mae Heldak | 27 | Wife | Saleswoman | Ohio |
| 26 | Fred Schroeder | 82 | Head | Laborer | At Sea |
| 27 | Fredericka Schroeder | 77 | Wife | — | Germany |
| 28 | William Schroeder | 63 | Nephew | Brick Layer | Illinois |
| 29 | John Decker | 41 | Head | Fireman | Michigan |
| 30 | Elizabeth Decker | 41 | Wife | Servant | Illinois |
| 31 | John Decker THIS PERSON | 17 | Son | Delivery Boy | Illinois |
| 32 | Anna Mae Decker | 15 | Daughter | — | Illinois |
| 33 | Ruth Decker | 13 | Daughter | — | Illinois |
| 34 | Shirley Decker | 10 | Daughter | — | Illinois |
| 35 | Betty Decker | 5 | Daughter | — | Illinois |
| 36 | Cornelius Decker | 53 | Brother | Laborer | Michigan |
| 37 | Walter Davis | 36 | Head | Laborer | South Carolina |
| 38 | Salena Davis | 34 | Wife | — | Illinois |
| 39 | Jesse Davis | 12 | Son | — | Illinois |
| 40 | Sarah Davis | 5 | Daughter | — | South Carolina |
Related Census Records
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)