JC
James Cooper — 1940 US Census Record
Model Tree available1940 United States Federal Census · Los-Angeles-County, California
Our Model Tree links this James Cooper across the 1920, 1930 and 1940 US Censuses in Los-Angeles-County, California (XGBoost, ~Confirmed), with identified parents Alexander & Harriet — first a son (b.~1915), then head of a 5-person household.
Age 25
b. ~1915
Male
Son
Born: California
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Los-Angeles-County, California |
| Surname | Cooper |
| Given Name | James L. |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 25 |
| Marital Status | Single |
| Birthplace | California |
| 1935 Residence (City) | Los Angeles city |
| 1935 Residence (County) | Los Angeles |
| Additional Details | |
| Occupation | New Worker |
| Income (1939) | 0 |
| Highest Grade | C-3 |
| 1935 Residence | Same place |
| Birth State | California |
| Birth Country | United States |
| Birthplace (normalized) | california |
| Occupation | New Worker |
| Township / Ward | Los Angeles City |
| Est. Birth Year | ~1915 |
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.
5 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to James | Age | Birth yr |
|---|---|---|---|---|
| Eleanor Cooper | Daughter | — | 29 | ~1911 |
| Alexander Cooper | Head | — | 54 | ~1886 |
| William Cooper | Son | — | 23 | ~1917 |
| James Cooper | Son | — | 25 | ~1915 |
| Harriet Cooper | Spouse | — | 55 | ~1885 |
Census Appearances
1920
Los Angeles, …
Son, age 5
Los Angeles, California · implied b. ~1915 — 5 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Cooper |
| Given Name | James |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 5 |
| Marital Status | Single |
| Birthplace | California |
| Father's Birthplace | England |
| Mother's Birthplace | California |
| Speaks English | Yes |
| Birth State | California |
| Birth Country | United States |
| Birthplace (normalized) | california |
1930
Los Angeles, …
Son, age 15
Los Angeles, California · implied b. ~1915 — 6 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | COOPER |
| Given Name | JAMES - L |
| Relationship to Head | SON |
| Sex | M |
| Color / Race | White |
| Age | 15 |
| Marital Status | Single |
| Birthplace | CALIFORNIA |
| Father's Birthplace | ENGLAND |
| Mother's Birthplace | CALIFORNIA |
| Occupation | NONE |
| Can Read/Write | Yes |
| Birth State | California |
| Birth Country | United States |
| Birthplace (normalized) | california |
1940
Los-Angeles-County, California
Son, age 25
Los-Angeles-County, California · implied b. ~1915 — 5 household members
| Surname | Cooper |
| Given Name | James L. |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 25 |
| Marital Status | Single |
| Birthplace | California |
| 1935 Residence (City) | Los Angeles city |
| 1935 Residence (County) | Los Angeles |
| Occupation | New Worker |
| Income (1939) | 0 |
| Highest Grade | C-3 |
| 1935 Residence | Same place |
| Birth State | California |
| Birth Country | United States |
| Birthplace (normalized) | california |
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 Cooper across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage. Identified parents: father Alexander Cooper (~0.92 confidence) and mother Harriet Cooper (~0.92 confidence). The pedigree spans 1 generation with 2 identified ancestors.
Show:
Gen 1
Parents
confidence ≈ 0.92
Father
Alexander Cooper
b. ~1886
Source father
● Household
· direct · ~0.92
Mother
Harriet Cooper
b. ~1889
Source mother
● Household
· direct · ~0.92
This person
Anchor record
James Cooper
Son · 1940 · age 25 · b. ~1915 · California
★ You are viewing this record
Sibling
William Cooper
Sibling · 1940 · age 23
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Eleanor Cooper
Sibling · 1940 · age 29
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 — Los-Angeles-County, California
Open full size
1940 US Federal Census — Los-Angeles-County, California
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-00393-00223)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Clyde Hudkins | 45 | Head | General Helper | Nebraska |
| 42 | Katherine Hudkins | 44 | Wife | — | Nebraska |
| 43 | Ace C. Hudkins | 12 | Son | — | California |
| 44 | Ab Hudkins | 43 | Brother | Actor | Nebraska |
| 45 | Francis J. Gabel | 36 | Head | Attorney | Kansas |
| 46 | Jeannette Gabel | 34 | Wife | — | Utah |
| 47 | Gretchen Gabel | 5 | Daughter | — | California |
| 48 | Pearl Wilkots | 35 | Maid | Housework | Michigan |
| 49 | Harold V. Avery | 40 | Head | Salesman | Illinois |
| 50 | Rose B. Avery | 38 | Wife | — | Italy |
| 51 | Bettina R. Avery | 8 | Daughter | — | Illinois |
| 52 | Nancy R. Avery | 5 | Daughter | — | Illinois |
| 53 | Mayme Valva | 42 | Sister-in-law | Dressmaker | Italy |
| 54 | Philip Valva | 18 | Nephew | — | Illinois |
| 55 | Lorin Nillyard | 38 | Head | Surgeon Physician | Kansas |
| 56 | Grace W. Nillyard | 32 | Wife | — | Minnesota |
| 57 | Larilyn Lee Nillyard | 2 | Daughter | — | California |
| 58 | Earlus Carson | 18 | Student Helper | Housework | Iowa |
| 59 | Harry J. Caldwell | 56 | Head | Electrical Engineer | Illinois |
| 60 | Edna B. Caldwell | 52 | Wife | — | Canada-Eng |
| 61 | Alexander Murray | 65 | Head | — | Virginia |
| 62 | Anne F. Murray | 64 | Wife | — | Virginia |
| 63 | Saunders | 40 | Head | Surgeon | Virginia |
| 64 | Ends Here | None | BLOCK | — | — |
| 65 | Franklin Wilson | 77 | Head | — | Michigan |
| 66 | Anna P. Wilson | 76 | Wife | — | Michigan |
| 67 | Alexander Cooper | 54 | Head | Sec. Treas. | England |
| 68 | Harriet A. Cooper | 55 | Wife | — | California |
| 69 | Eleanor Cooper | 29 | Daughter | — | California |
| 70 | James L. Cooper THIS PERSON | 25 | Son | New Worker | California |
| 71 | William C. Cooper | 23 | Son | — | California |
| 72 | Ed E. Williams | 67 | Head | — | Sweden |
| 73 | Martha E. Williams | 65 | Wife | — | Iowa |
| 74 | Lucille E. Williams | 36 | Daughter | — | Iowa |
| 75 | Hulda A. Overmann | 76 | Head | — | Germany |
| 76 | Marie A. Overmann | 49 | Daughter | Saleslady | Ohio |
| 77 | Elsie Overmann | 49 | Daughter | Saleslady | Ohio |
| 78 | Cecelia Kleisteiber | 42 | Daughter | — | Ohio |
| 79 | Alma Mayfield | 61 | Head | — | Texas |
| 80 | Joseph C. Bevell | 52 | Head | Proprietor | Kansas |
Pedigree Summary
James + 2 siblings
Gen 1 · 2 parents
~0.92
Max depth 4 (1900–1950 window)
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)