JC
James Cobb — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Cook-County, Illinois
Our Model Tree links this James Cobb across the 1930 and 1940 US Censuses in Cook-County, Illinois (XGBoost, ~Confirmed) — first a son (b.~1929), then head of a 10-person household.
Age 11
b. ~1929
Male
Son
Born: Illinois
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Cook-County, Illinois |
| Surname | Cobb |
| Given Name | James |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | Black |
| Age | 11 |
| Marital Status | Single |
| Birthplace | Illinois |
| 1935 Residence (City) | Chicago |
| 1935 Residence (County) | Cook |
| Additional Details | |
| Highest Grade | 3 |
| 1935 Residence | Same place |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
| Township / Ward | Chicago |
| Est. Birth Year | ~1929 |
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 James | Age | Birth yr |
|---|---|---|---|---|
| James Cobb | Son | — | 11 | ~1929 |
| Margarette Cobb | Daughter | — | 13 | ~1927 |
| Delores Cobb | Daughter | — | ~1940 | |
| Henry Cobb | Son | — | 14 | ~1926 |
| Helen Cobb | Daughter | — | 2 | ~1938 |
| Gladys Cobb | Daughter | — | 6 | ~1934 |
| Annie Cobb | Daughter | — | 16 | ~1924 |
| Andrew Cobb | Son | — | 4 | ~1936 |
| Flora Cobb | Spouse | — | 38 | ~1902 |
| Willie Cobb | Son | — | 12 | ~1928 |
Census Appearances
1930
Cook, Illinois
Son, age 5
Cook, Illinois · implied b. ~1925 — 7 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Cobb |
| Given Name | James |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | Black |
| Age | 5 |
| Marital Status | Single |
| Birthplace | Illinois |
| Father's Birthplace | Illinois |
| Mother's Birthplace | Illinois |
| Can Read/Write | No |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1940
Cook-County, Illinois
Son, age 11
Cook-County, Illinois · implied b. ~1929 — 10 household members
| Surname | Cobb |
| Given Name | James |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | Black |
| Age | 11 |
| Marital Status | Single |
| Birthplace | Illinois |
| 1935 Residence (City) | Chicago |
| 1935 Residence (County) | Cook |
| Highest Grade | 3 |
| 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 James Cobb across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
James Cobb
Son · 1940 · age 11 · b. ~1929 · Illinois
★ You are viewing this record
Sibling
Helen Cobb
Sibling · 1940 · age 2
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Gladys Cobb
Sibling · 1940 · age 6
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Henry Cobb
Sibling · 1940 · age 14
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Annie Cobb
Sibling · 1940 · age 16
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Margarette Cobb
Sibling · 1940 · age 13
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Delores Cobb
Sibling · 1940 · age
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Andrew Cobb
Sibling · 1940 · age 4
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Willie Cobb
Sibling · 1940 · age 12
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
10 people indexed on this census page (nara:1940:m-t0627-00922-00500)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Flora Cobb | 38 | Wife | Music Teacher | Mississippi |
| 42 | Annie Mae Cobb | 16 | Daughter | Music Teacher | Illinois |
| 43 | Henry Cobb | 14 | Son | Music Teacher | Illinois |
| 44 | Margarette Cobb | 13 | Daughter | — | Illinois |
| 45 | Willie Cobb | 12 | Son | — | Illinois |
| 46 | James Cobb THIS PERSON | 11 | Son | — | Illinois |
| 47 | Gladys Cobb | 6 | Daughter | — | Illinois |
| 48 | Andrew Cobb | 4 | Son | — | Illinois |
| 49 | Helen Cobb | 2 | Daughter | — | Illinois |
| 50 | Delores Cobb | 0 | Daughter | — | 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)