MJ
Mary Jensen — 1930 US Census Record
Linked across censuses1930 United States Federal Census · Alameda, California
Our Model Tree links this Mary Jensen across the 1930 and 1940 US Censuses in Alameda, California (XGBoost, ~Confirmed) — first a daughter (b.~1914), then head of a 12-person household.
Age 16
b. ~1914
Female
Daughter
Born: California
Single
1930 Census Record Details
| Census Year | 1930 |
| Location | Alameda, California |
| Surname | Jensen |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 16 |
| Marital Status | Single |
| Birthplace | California |
| Father's Birthplace | Denmark |
| Mother's Birthplace | Denmark |
| Additional Details | |
| Can Read/Write | Yes |
| Birth State | California |
| Birth Country | United States |
| Birthplace (normalized) | california |
| Township / Ward | Oakland |
| 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.
12 people recorded at the same address in the 1930 census.
| Name | Relation to head | Relative to Mary | Age | Birth yr |
|---|---|---|---|---|
| Ruth Jensen | Daughter | — | 4 | ~1926 |
| Alice Jensen | Daughter | — | 8 | ~1922 |
| Mary Jensen | Daughter | — | 16 | ~1914 |
| Emma Jensen | Daughter | — | 12 | ~1918 |
| Jens Jensen | Head | — | 50 | ~1880 |
| George Jensen | Son | — | 10 | ~1920 |
| Chris Jensen | Son | — | 18 | ~1912 |
| Henry Jensen | Son | — | 6 | ~1924 |
| Robert Jensen | Son | — | 2 | ~1928 |
| John Jensen | Son | — | 14 | ~1916 |
| Baby Jensen | Son | — | ~1930 | |
| Anna Jensen | Spouse | — | 45 | ~1885 |
Census Appearances
1930
Alameda, California
Daughter, age 16
Alameda, California · implied b. ~1914 — 12 household members
| Surname | Jensen |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 16 |
| Marital Status | Single |
| Birthplace | California |
| Father's Birthplace | Denmark |
| Mother's Birthplace | Denmark |
| Can Read/Write | Yes |
| Birth State | California |
| Birth Country | United States |
| Birthplace (normalized) | california |
1940
Alameda-County, California
Daughter, age 25
Alameda-County, California · implied b. ~1915 — 5 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Jensen |
| Given Name | Margaret |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 25 |
| Marital Status | Single |
| Birthplace | California |
| 1935 Residence (County) | Alameda |
| Occupation | 48 |
| Industry | Beautician |
| Class of Worker | Beauty Shop |
| Highest Grade | Hs 4 |
| 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 Mary Jensen across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
Mary Jensen
Daughter · 1930 · age 16 · b. ~1914 · California
★ You are viewing this record
Sibling
John Jensen
Sibling · 1930 · age 14
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Emma Jensen
Sibling · 1930 · age 12
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Ruth Jensen
Sibling · 1930 · age 4
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Alice Jensen
Sibling · 1930 · age 8
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Henry Jensen
Sibling · 1930 · age 6
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
George Jensen
Sibling · 1930 · age 10
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Robert Jensen
Sibling · 1930 · age 2
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Chris Jensen
Sibling · 1930 · age 18
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Baby Jensen
Sibling · 1930 · age
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
1930 US Federal Census — Alameda, California
Open full size
1930 US Federal Census — Alameda, California
Page Contents
50 people indexed on this census page (ia:1930:15thcensuspopula100unit:0218)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Hans Hansen | 45 | Head | Carpenter | Denmark |
| 2 | Anna Hansen | 42 | Wife | — | Denmark |
| 3 | Arthur Hansen | 18 | Son | Laborer | California |
| 4 | Elmer Hansen | 16 | Son | Laborer | California |
| 5 | Helen Hansen | 14 | Daughter | — | California |
| 6 | Alice Hansen | 12 | Daughter | — | California |
| 7 | Dorothy Hansen | 10 | Daughter | — | California |
| 8 | Harold Hansen | 8 | Son | — | California |
| 9 | Robert Hansen | 6 | Son | — | California |
| 10 | Margaret Hansen | 4 | Daughter | — | California |
| 11 | Richard Hansen | 2 | Son | — | California |
| 12 | Nels Nelson | 52 | Head | Farmer | Sweden |
| 13 | Hilda Nelson | 48 | Wife | — | Sweden |
| 14 | Carl Nelson | 19 | Son | Laborer | California |
| 15 | Esther Nelson | 17 | Daughter | — | California |
| 16 | Ruth Nelson | 15 | Daughter | — | California |
| 17 | Oscar Nelson | 13 | Son | — | California |
| 18 | Edith Nelson | 11 | Daughter | — | California |
| 19 | George Nelson | 9 | Son | — | California |
| 20 | Alice Nelson | 7 | Daughter | — | California |
| 21 | Mary Nelson | 5 | Daughter | — | California |
| 22 | John Nelson | 3 | Son | — | California |
| 23 | Baby Nelson | 0 | Son | — | California |
| 24 | Peter Peterson | 60 | Head | Farmer | Denmark |
| 25 | Mary Peterson | 55 | Wife | — | Denmark |
| 26 | Chris Peterson | 24 | Son | Laborer | California |
| 27 | Anna Peterson | 22 | Daughter | — | California |
| 28 | John Peterson | 20 | Son | Laborer | California |
| 29 | Mabel Peterson | 18 | Daughter | — | California |
| 30 | William Peterson | 16 | Son | Laborer | California |
| 31 | Emma Peterson | 14 | Daughter | — | California |
| 32 | George Peterson | 12 | Son | — | California |
| 33 | Alice Peterson | 10 | Daughter | — | California |
| 34 | Henry Peterson | 8 | Son | — | California |
| 35 | Ruth Peterson | 6 | Daughter | — | California |
| 36 | Robert Peterson | 4 | Son | — | California |
| 37 | Margaret Peterson | 2 | Daughter | — | California |
| 38 | Baby Peterson | 0 | Son | — | California |
| 39 | Jens Jensen | 50 | Head | Farmer | Denmark |
| 40 | Anna Jensen | 45 | Wife | — | Denmark |
| 41 | Chris Jensen | 18 | Son | Laborer | California |
| 42 | Mary Jensen THIS PERSON | 16 | Daughter | — | California |
| 43 | John Jensen | 14 | Son | — | California |
| 44 | Emma Jensen | 12 | Daughter | — | California |
| 45 | George Jensen | 10 | Son | — | California |
| 46 | Alice Jensen | 8 | Daughter | — | California |
| 47 | Henry Jensen | 6 | Son | — | California |
| 48 | Ruth Jensen | 4 | Daughter | — | California |
| 49 | Robert Jensen | 2 | Son | — | California |
| 50 | Baby Jensen | 0 | Son | — | California |
About This Record & Model Tree
This record was independently indexed by YourRoots from the 1930 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)