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John Cobb — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Knox-County, Kentucky
Our Model Tree links this John Cobb across the 1930 and 1940 US Censuses in Knox-County, Kentucky (XGBoost, ~Confirmed) — first a son (b.~1930), then head of a 8-person household.
Age 10
b. ~1930
Male
Son
Born: Kentucky
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Knox-County, Kentucky |
| Surname | Cobb |
| Given Name | John Henry |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 10 |
| Marital Status | Single |
| Birthplace | Kentucky |
| 1935 Residence (City) | Some house |
| 1935 Residence (County) | Some house |
| Additional Details | |
| Industry | 0 |
| Highest Grade | No 4 |
| 1935 Residence | Same place |
| Birth State | Kentucky |
| Birth Country | United States |
| Birthplace (normalized) | kentucky |
| Township / Ward | Mag Dist 5 |
| Est. Birth Year | ~1930 |
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 |
|---|---|---|---|---|
| Marion Cobb | Son | — | 6 | ~1934 |
| Kenneth Cobb | Son | — | 1 | ~1939 |
| Henry Cobb | Head | — | 54 | ~1886 |
| Ellen Cobb | Daughter | — | 14 | ~1926 |
| Maud Cobb | Daughter | — | 17 | ~1923 |
| Martha Cobb | Spouse | — | 42 | ~1898 |
| John Cobb | Son | — | 10 | ~1930 |
| Elizabeth Cobb | Daughter | — | 13 | ~1927 |
Census Appearances
1930
Knox, Kentucky
Son, age 1
Knox, Kentucky · implied b. ~1929 — 3 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Cobb |
| Given Name | John H |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 1 |
| Marital Status | Single |
| Birthplace | Kentucky |
| Father's Birthplace | Kentucky |
| Mother's Birthplace | Kentucky |
| Can Read/Write | No |
| Birth State | Kentucky |
| Birth Country | United States |
| Birthplace (normalized) | kentucky |
1940
Knox-County, Kentucky
Son, age 10
Knox-County, Kentucky · implied b. ~1930 — 8 household members
| Surname | Cobb |
| Given Name | John Henry |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 10 |
| Marital Status | Single |
| Birthplace | Kentucky |
| 1935 Residence (City) | Some house |
| 1935 Residence (County) | Some house |
| Industry | 0 |
| Highest Grade | No 4 |
| 1935 Residence | Same place |
| Birth State | Kentucky |
| Birth Country | United States |
| Birthplace (normalized) | kentucky |
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 Cobb across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
John Cobb
Son · 1940 · age 10 · b. ~1930 · Kentucky
★ You are viewing this record
Sibling
Kenneth Cobb
Sibling · 1940 · age 1
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Ellen Cobb
Sibling · 1940 · age 14
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Elizabeth Cobb
Sibling · 1940 · age 13
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Marion Cobb
Sibling · 1940 · age 6
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Maud Cobb
Sibling · 1940 · age 17
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 — Knox-County, Kentucky
Open full size
1940 US Federal Census — Knox-County, Kentucky
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-01326-01039)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Dorothy Halcomb | 12 | Daughter | — | Kentucky |
| 42 | Nannie B. Halcomb | 8 | Daughter | — | Kentucky |
| 43 | Henry Cobb | 54 | Head | — | Kentucky |
| 44 | Martha Cobb | 42 | Wife | H S | Kentucky |
| 45 | Maud Cobb | 17 | Daughter | H S | Kentucky |
| 46 | Ellen Cobb | 14 | Daughter | H S | Kentucky |
| 47 | Elizabeth Cobb | 13 | Daughter | — | Kentucky |
| 48 | John Henry Cobb THIS PERSON | 10 | Son | — | Kentucky |
| 49 | Marion Cobb | 6 | Son | — | Kentucky |
| 50 | Kenneth Gilbert Cobb | 1 | Son | — | Kentucky |
| 51 | J. H. Halcomb | 24 | Head | Farmer | Kentucky |
| 52 | Ruby Halcomb | 21 | Wife | H S | Kentucky |
| 53 | Dallas Wayne Halcomb | 0 | Son | — | Kentucky |
| 54 | Henry Childers | 75 | Head | Farmer | Kentucky |
| 55 | Creed Childers | 23 | Son | Labour | Kentucky |
| 56 | Zonia Childers | 19 | Wife | H S | Kentucky |
| 57 | Hersel Childers | 0 | Son | — | Kentucky |
| 58 | J. H. Davidson | 45 | Head | Farmer | Kentucky |
| 59 | Sadie Davidson | 42 | Wife | H S | Kentucky |
| 60 | John Davidson | 18 | Son | Labour | Kentucky |
| 61 | Clona Davidson | 16 | Daughter | — | Kentucky |
| 62 | Edward Davidson | 10 | Son | — | Kentucky |
| 63 | Kinley Davidson | 6 | Son | — | Kentucky |
| 64 | Delmar Davidson | 4 | Son | — | Kentucky |
| 65 | Emery Davidson | 38 | Head | Farmer | Kentucky |
| 66 | Martha Davidson | 26 | Wife | H S | Kentucky |
| 67 | Priscila Davidson | 8 | Daughter | — | Kentucky |
| 68 | Allie Davidson | 7 | Daughter | — | Kentucky |
| 69 | Jr. H. Davidson | 69 | Head | Farmer | Kentucky |
| 70 | Laura Davidson | 67 | Wife | H S | Kentucky |
| 71 | Rachel Gallett | 58 | Sister | — | Kentucky |
| 72 | Tucker Smith | 51 | Head | Farmer | Kentucky |
| 73 | Denver Smith | 20 | Son | Labour | Kentucky |
| 74 | Pearlie Smith | 18 | Daughter | H S | Kentucky |
| 75 | Vinnie Smith | 50 | Wife | H S | Kentucky |
| 76 | Joe Smith | 14 | Son | H S | Kentucky |
| 77 | Henry T Smith | 11 | Son | — | Kentucky |
| 78 | Clarence Smith | 9 | Son | — | Kentucky |
| 79 | Yaulie Smith | 6 | Daughter | — | Kentucky |
| 80 | Lola Mae Smith | 5 | Daughter | — | Kentucky |
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)