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Mary Lopez — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Maricopa-County, Arizona
Our Model Tree links this Mary Lopez across the 1930 and 1940 US Censuses in Maricopa-County, Arizona (XGBoost, ~Confirmed) — first a daughter (b.~1928), then head of a 8-person household.
Age 12
b. ~1928
Female
Daughter
Born: Arizona
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Maricopa-County, Arizona |
| Surname | Lopez |
| Given Name | Mary A |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 12 |
| Marital Status | Single |
| Birthplace | Arizona |
| 1935 Residence (City) | Phoenix City |
| 1935 Residence (County) | MARICOPA |
| Additional Details | |
| Highest Grade | Yes 7 |
| 1935 Residence | Same house |
| Birth State | Arizona |
| Birth Country | United States |
| Birthplace (normalized) | arizona |
| Township / Ward | Phoenix City |
| Est. Birth Year | ~1928 |
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 Mary | Age | Birth yr |
|---|---|---|---|---|
| Edward Lopez | Son | — | 9 | ~1931 |
| Thomas Lopez | Son | — | 10 | ~1930 |
| Freddie Lopez | Son | — | 4 | ~1936 |
| Thomas Lopez | Head | — | 36 | ~1904 |
| Theresa Lopez | Daughter | — | 1 | ~1939 |
| Mary Lopez | Daughter | — | 12 | ~1928 |
| Deloras Lopez | Spouse | — | 31 | ~1909 |
| Frank Lopez | Son | — | 5 | ~1935 |
Census Appearances
1930
Maricopa, Arizona
Daughter, age 2
Maricopa, Arizona · implied b. ~1928 — 4 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Lopez |
| Given Name | Mary A. |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | Mexican |
| Age | 2 |
| Marital Status | Single |
| Birthplace | Arizona |
| Father's Birthplace | Mexico |
| Mother's Birthplace | Arizona |
| Birth State | Arizona |
| Birth Country | United States |
| Birthplace (normalized) | arizona |
1940
Maricopa-County, Arizona
Daughter, age 12
Maricopa-County, Arizona · implied b. ~1928 — 8 household members
| Surname | Lopez |
| Given Name | Mary A |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 12 |
| Marital Status | Single |
| Birthplace | Arizona |
| 1935 Residence (City) | Phoenix City |
| 1935 Residence (County) | MARICOPA |
| Highest Grade | Yes 7 |
| 1935 Residence | Same house |
| Birth State | Arizona |
| Birth Country | United States |
| Birthplace (normalized) | arizona |
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 Lopez across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
Mary Lopez
Daughter · 1940 · age 12 · b. ~1928 · Arizona
★ You are viewing this record
Sibling
Theresa Lopez
Sibling · 1940 · age 1
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Frank Lopez
Sibling · 1940 · age 5
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Thomas Lopez
Sibling · 1940 · age 10
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Edward Lopez
Sibling · 1940 · age 9
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Freddie Lopez
Sibling · 1940 · age 4
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 — Maricopa-County, Arizona
Open full size
1940 US Federal Census — Maricopa-County, Arizona
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-00105-00804)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Raymond Hill | 3 | Son | — | Oklahoma |
| 2 | William Hill | 2 | Son | — | Arizona |
| 3 | Jesus Acuna | 39 | Head | Laborer | Arizona |
| 4 | Julia Acuna | 31 | Wife | — | Arizona |
| 5 | Elbira Acuna | 11 | Daughter | — | Arizona |
| 6 | Jimmie Acuna | 13 | Son | — | Arizona |
| 7 | Jesus Jr Acuna | 8 | Son | — | Arizona |
| 8 | Mildred Acuna | 6 | Daughter | — | Arizona |
| 9 | Katty Acuna | 3 | Daughter | — | Arizona |
| 10 | Sallie Acuna | 1 | Daughter | — | Arizona |
| 11 | Edro Olivias | 40 | Head | Hop Carrier | Arizona |
| 12 | Rita Olivias | 39 | Wife | — | Arizona |
| 13 | Janie Olivias | 14 | Daughter | — | Arizona |
| 14 | Ygnaigo Lugo | 20 | Son-in-law | Laborer | Arizona |
| 15 | Arura Lugo | 17 | Daughter | — | Arizona |
| 16 | Ygnaigo Jr Lugo | 0 | Grand-son | — | Arizona |
| 17 | Thomas R Lopez | 36 | Head | Clerk | Mexico |
| 18 | Deloras Lopez | 31 | Wife | — | Arizona |
| 19 | Mary A Lopez THIS PERSON | 12 | Daughter | — | Arizona |
| 20 | Thomas Jr Lopez | 10 | Son | — | Arizona |
| 21 | Edward Lopez | 9 | Son | — | Arizona |
| 22 | Frank Lopez | 5 | Son | — | Arizona |
| 23 | Freddie Lopez | 4 | Son | — | Arizona |
| 24 | Theresa Lopez | 1 | Daughter | — | Arizona |
| 25 | Joe Peralta | 40 | Head | Laborer | Mexico |
| 26 | Quina Peralta | 44 | Wife | — | Arizona |
| 27 | Angelita Peralta | 17 | Daughter | — | Arizona |
| 28 | Joe Jr Peralta | 13 | Son | — | Arizona |
| 29 | Ricardo Canez | 38 | Head | Truck Driver | Mexico |
| 30 | Mercy Canez | 34 | Wife | — | Mexico |
| 31 | Francis Canez | 16 | Daughter | — | Arizona |
| 32 | Richard Canez | 13 | Son | — | Arizona |
| 33 | Esparanzo Canez | 9 | Son | — | Arizona |
| 34 | Nellie Canez | 4 | Daughter | — | Arizona |
| 35 | Ling Fong | 54 | Head | Owner | California |
| 36 | Theresa Fong | 44 | Wife | Clerk | Arizona |
| 37 | Thelma Fong | 25 | Daughter | Clerk | Arizona |
| 38 | Chonaita Fong | 16 | Daughter | — | Arizona |
| 39 | Rashal Fong | 8 | Daughter | — | Arizona |
| 40 | Phillips Fong | 14 | Son | — | Arizona |
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)