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Mary Mcmahon — 1930 US Census Record
Linked across censuses1930 United States Federal Census · Salem, New Jersey
Our Model Tree links this Mary Mcmahon across the 1920 and 1930 US Censuses in Salem, New Jersey (XGBoost, ~Confirmed) — first a daughter (b.~1916), then head of a 10-person household.
Age 14
b. ~1916
Female
Daughter
Born: New Jersey
Single
1930 Census Record Details
| Census Year | 1930 |
| Location | Salem, New Jersey |
| Surname | McMahon |
| Given Name | Mary H. |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 14 |
| Marital Status | Single |
| Birthplace | New Jersey |
| Father's Birthplace | New Jersey |
| Mother's Birthplace | New Jersey |
| Additional Details | |
| Can Read/Write | Yes |
| Birth State | New Jersey |
| Birth Country | United States |
| Birthplace (normalized) | new jersey |
| Township / Ward | Pennsgrove Borough |
| Est. Birth Year | ~1916 |
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 1930 census.
| Name | Relation to head | Relative to Mary | Age | Birth yr |
|---|---|---|---|---|
| Lucille Mcmahon | Daughter | — | 5 | ~1925 |
| Mary Mcmahon | Daughter | — | 14 | ~1916 |
| Anna Brennan | Daughter | — | 19 | ~1911 |
| Thomas Mcmahon | Head | — | 47 | ~1883 |
| Margaret Brennan | Other | — | 3 | ~1927 |
| Leo Mcmahon | Son | — | 10 | ~1920 |
| William Mcmahon | Son | — | 17 | ~1913 |
| Lawrence Mcmahon | Son | — | 10 | ~1920 |
| Thomas Mcmahon | Son | — | 21 | ~1909 |
| Margaret Mcmahon | Spouse | — | 42 | ~1888 |
Census Appearances
1920
Salem, New …
Daughter, age 4
Salem, New Jersey · implied b. ~1916 — 8 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | McMahon |
| Given Name | Mary |
| Relationship to Head | daughter |
| Sex | F |
| Color / Race | White |
| Age | 4 |
| Marital Status | Single |
| Birthplace | New Jersey |
| Father's Birthplace | New Jersey |
| Mother's Birthplace | New Jersey |
| Occupation | none |
| Birth State | New Jersey |
| Birth Country | United States |
| Birthplace (normalized) | new jersey |
1930
Salem, New …
Daughter, age 14
Salem, New Jersey · implied b. ~1916 — 10 household members
| Surname | McMahon |
| Given Name | Mary H. |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 14 |
| Marital Status | Single |
| Birthplace | New Jersey |
| Father's Birthplace | New Jersey |
| Mother's Birthplace | New Jersey |
| Can Read/Write | Yes |
| Birth State | New Jersey |
| Birth Country | United States |
| Birthplace (normalized) | new jersey |
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 Mcmahon across 2 US Census years (1920 and 1930) in Salem, New Jersey, using XGBoost record linkage.
Show:
This person
Anchor record
Mary Mcmahon
Daughter · 1930 · age 14 · b. ~1916 · New Jersey
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Sibling
William Mcmahon
Sibling · 1930 · age 17
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Anna Brennan
Sibling · 1930 · age 19
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Lucille Mcmahon
Sibling · 1930 · age 5
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Thomas Mcmahon
Sibling · 1930 · age 21
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Lawrence Mcmahon
Sibling · 1930 · age 10
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Leo Mcmahon
Sibling · 1930 · age 10
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 — Salem, New Jersey
Open full size
1930 US Federal Census — Salem, New Jersey
Page Contents
50 people indexed on this census page (ia:1930:newjerseycensus00reel1382:0861)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 51 | Samuel H. Simkins | 31 | Head | Electrician | New Jersey |
| 52 | Kathleen Simkins | 26 | Wife | — | Scotland |
| 53 | Robert S. Simkins | 5 | Son | — | Pennsylvania |
| 54 | William C. Simkins | 4 | Son | — | Pennsylvania |
| 55 | Samuel H. Jr. Simkins | 2 | Son | — | New Jersey |
| 56 | Joseph R. Simkins | 0 | Son | — | New Jersey |
| 57 | Michael A. Marlboro | 33 | Head | Millwright | New Jersey |
| 58 | Mary Marlboro | 33 | Wife | — | New Jersey |
| 59 | Michael Marlboro | 12 | Son | — | New Jersey |
| 60 | Emma J. Marlboro | 11 | Daughter | — | New Jersey |
| 61 | Susan Marlboro | 7 | Daughter | — | New Jersey |
| 62 | William Hughes | 31 | Boarder | Rigger | New Jersey |
| 63 | Ernest R. Bentz | 34 | Head | Machine Hand | Washington |
| 64 | Mary E. Bentz | 30 | Wife | — | Maryland |
| 65 | Mildred Bentz | 8 | Daughter | — | Maryland |
| 66 | Ernest Bentz | 6 | Son | — | Maryland |
| 67 | Theresa Graham | 43 | Head | — | Pennsylvania |
| 68 | George F. Graham | 21 | Son | Operator | Pennsylvania |
| 69 | Raymond Graham | 17 | Son | Waiter | New Jersey |
| 70 | Eldred Graham | 15 | Son | — | Pennsylvania |
| 71 | Anna M. Graham | 9 | Daughter | — | Pennsylvania |
| 72 | Joseph Myer | 19 | Boarder | Checker | New Jersey |
| 73 | John M. Thomas | 64 | Head | Farmer | Florida |
| 74 | Ella Thomas | 57 | Wife | — | Pennsylvania |
| 75 | Florence E. Thomas | 30 | Daughter | Servant | Pennsylvania |
| 76 | Edna Thomas | 21 | Daughter | — | Pennsylvania |
| 77 | Pearce Barnett | 18 | Boarder | — | Virginia |
| 78 | William Barnett | 23 | Boarder | Laborer | Virginia |
| 79 | Percy A. Barnett | 2 | Boarder | Laborer | Virginia |
| 80 | Barnett | 1 | Boarder | Servant | Virginia |
| 81 | Emily R. Thompson | 55 | Head | — | New Jersey |
| 82 | Carol G. Yarber | 9 | Granddaughter | — | Pennsylvania |
| 83 | Patrick H. Yarber | 7 | Grandson | — | New Jersey |
| 84 | Morris H. King | 29 | Head | Shipping Clerk | Delaware |
| 85 | Edna S. King | 23 | Wife | Stenographer | Pennsylvania |
| 86 | Thomas Battershall | 47 | Head | Machinist | Pennsylvania |
| 87 | Edna W. Battershall | 41 | Wife | — | New Jersey |
| 88 | Charles S. Battershall | 15 | Son | — | New Jersey |
| 89 | Charlotte R. Battershall | 75 | Mother | — | New Jersey |
| 90 | Thomas Mcmahon | 47 | Head | Builder | New Jersey |
| 91 | Margaret M. Mcmahon | 42 | Wife | — | New Jersey |
| 92 | Thomas J. Mcmahon | 21 | Son | Electrician | New Jersey |
| 93 | Anna Brennan | 19 | Daughter | Sales Woman | New Jersey |
| 94 | William H. Mcmahon | 17 | Son | Pharmacist Asst | New Jersey |
| 95 | Mary H. Mcmahon THIS PERSON | 14 | Daughter | — | New Jersey |
| 96 | Leo Mcmahon | 10 | Son | — | New Jersey |
| 97 | Lawrence Mcmahon | 10 | Son | — | New Jersey |
| 98 | Lucille J. Mcmahon | 5 | Daughter | — | New Jersey |
| 99 | Margaret H. Brennan | 3 | Granddaughter | — | New Jersey |
| 100 | James Hasko | 63 | Head | Laborer | Delaware |
Related Census Records
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)