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William Kirby — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Cook-County, Illinois
Our Model Tree links this William Kirby across the 1930 and 1940 US Censuses in Cook-County, Illinois (XGBoost, ~Confirmed) — first a son (b.~1914), then head of a 7-person household.
Age 26
b. ~1914
Male
Son
Born: Illinois
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Cook-County, Illinois |
| Surname | Kirby |
| Given Name | William J. |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 26 |
| Marital Status | Single |
| Birthplace | Illinois |
| 1935 Residence (City) | Chicago City |
| 1935 Residence (County) | Cook |
| Additional Details | |
| Occupation | Laborer |
| Industry | Building |
| Class of Worker | PW |
| Hours Worked | 40 |
| Income (1939) | 1000 |
| Highest Grade | C 2 |
| 1935 Residence | Same Place |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
| Occupation | Laborer |
| Township / Ward | Chicago City |
| Est. Birth Year | ~1914 |
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.
7 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to William | Age | Birth yr |
|---|---|---|---|---|
| James Kirby | Son | — | 33 | ~1907 |
| James Kirby | Head | — | 60 | ~1880 |
| Jean Kirby | Daughter | — | 20 | ~1920 |
| John Kirby | Son | — | 35 | ~1905 |
| Mildred Kirby | Daughter | — | 31 | ~1909 |
| Mary Kirby | Spouse | — | 60 | ~1880 |
| William Kirby | Son | — | 26 | ~1914 |
Census Appearances
1930
Cook, Illinois
Son, age 15
Cook, Illinois · implied b. ~1915 — 8 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Kirby |
| Given Name | William |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 15 |
| Marital Status | Single |
| Birthplace | Illinois |
| Father's Birthplace | Canada-French |
| Mother's Birthplace | Illinois |
| Can Read/Write | Yes |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1940
Cook-County, Illinois
Son, age 26
Cook-County, Illinois · implied b. ~1914 — 7 household members
| Surname | Kirby |
| Given Name | William J. |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 26 |
| Marital Status | Single |
| Birthplace | Illinois |
| 1935 Residence (City) | Chicago City |
| 1935 Residence (County) | Cook |
| Occupation | Laborer |
| Industry | Building |
| Class of Worker | PW |
| Hours Worked | 40 |
| Income (1939) | 1000 |
| Highest Grade | C 2 |
| 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 William Kirby across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
William Kirby
Son · 1940 · age 26 · b. ~1914 · Illinois
★ You are viewing this record
Sibling
James Kirby
Sibling · 1940 · age 33
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Jean Kirby
Sibling · 1940 · age 20
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Mildred Kirby
Sibling · 1940 · age 31
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
John Kirby
Sibling · 1940 · age 35
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-t0627-00934-00469)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Isadore Hanan | 48 | Head | Cutter | Illinois |
| 42 | Elizabeth Hanan | 52 | Wife | — | Lithuania |
| 43 | Hortense Hanan | 20 | Daughter | Secretary | Illinois |
| 44 | Julia Friedman | 48 | Sister-in-law | Saleslady | Lithuania |
| 45 | William Mcduffie | 78 | Head | — | England |
| 46 | William James Mcduffie | 48 | Son | — | New York |
| 47 | Mary Emma Mcduffie | 43 | Daughter | Teacher | New York |
| 48 | James F. Kirby | 60 | Head | — | Canada-British |
| 49 | Mary G. Kirby | 60 | Wife | — | Illinois |
| 50 | James E. Kirby | 33 | Son | Postal Clerk | Illinois |
| 51 | John D. Kirby | 35 | Son | Truck Driver | Illinois |
| 52 | Mildred M. Kirby | 31 | Daughter | School Clerk | Illinois |
| 53 | William J. Kirby THIS PERSON | 26 | Son | Laborer | Illinois |
| 54 | Jean Kirby | 20 | Daughter | Stenographer | Illinois |
| 55 | Nicholas Johnson | 60 | Head | Electrical Engineer | Wisconsin |
| 56 | Mary Johnson | 55 | Wife | — | Kentucky |
| 57 | Robert J. Humphrey | 35 | Son-in-law | Route Driver | Illinois |
| 58 | Alice Humphrey | 55 | Lodger | Maid | Kentucky |
| 59 | Reno Alexander | 69 | Head | Collector | Missouri |
| 60 | Pauline Alexander | 59 | Wife | — | Pennsylvania |
| 61 | Donald B. Alexander | 31 | Son | Statistician | Illinois |
| 62 | Raymond Carroll | 40 | Step-son | Musician | Massachusetts |
| 63 | James Welches | 39 | Head | Research | Illinois |
| 64 | Alice Welches | 25 | Wife | — | Illinois |
| 65 | Betty Welches | 3 | Daughter | — | Illinois |
| 66 | Louis J. Goldner | 34 | Head | Broker | New York |
| 67 | Marie Goldner | 26 | Wife | — | Illinois |
| 68 | Jay Goldner | 2 | Son | — | Illinois |
| 69 | James Goldner | 0 | Son | — | Illinois |
| 70 | Gustav Altmann | 42 | Head | — | Germany |
| 71 | Kurt Altmann | 20 | Son | — | Germany |
| 72 | Horst Altmann | 17 | Son | Cabinet Maker | Germany |
| 73 | Dorothy Altmann | 11 | Daughter | — | Germany |
| 74 | — | None | — | — | — |
| 75 | Marguerite Vervan | 57 | Head | — | Minnesota |
| 76 | Louis Vervan | 19 | Son | Salesman | Illinois |
| 77 | Mary Humphrey | 55 | Lodger | Saleslady | Illinois |
| 78 | Nathan Hoffman | 60 | Head | Proprietor | Russia |
| 79 | Bertha Hoffman | 55 | Wife | — | Russia |
| 80 | Murlin Hoffman | 27 | Daughter | — | Illinois |
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)