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John Duffy — 1930 US Census Record
Model Tree available1930 United States Federal Census · Merrimack, New Hampshire
Our Model Tree links this John Duffy across the 1910, 1920 and 1930 US Censuses in Merrimack, New Hampshire (XGBoost, ~Confirmed), with identified parents Thomas & Thomas — first a son (b.~1910), then head of a 6-person household.
Age 20
b. ~1910
Male
Son
Born: New Hampshire
Single
1930 Census Record Details
| Census Year | 1930 |
| Location | Merrimack, New Hampshire |
| Surname | Duffy |
| Given Name | John G |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 20 |
| Marital Status | Single |
| Birthplace | New Hampshire |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Additional Details | |
| Occupation | Laborer |
| Industry | General Work |
| Class of Worker | W |
| Can Read/Write | Yes |
| Birth State | New Hampshire |
| Birth Country | United States |
| Birthplace (normalized) | new hampshire |
| Occupation | Laborer |
| Township / Ward | Concord City |
| Est. Birth Year | ~1910 |
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.
6 people recorded at the same address in the 1930 census.
| Name | Relation to head | Relative to John | Age | Birth yr |
|---|---|---|---|---|
| Katherine Duffy | Daughter | — | 23 | ~1907 |
| Thomas Duffy | Head | — | 45 | ~1885 |
| Agnes Duffy | Other | — | 44 | ~1886 |
| John Duffy | Son | — | 20 | ~1910 |
| Martin Duffy | Son | — | 22 | ~1908 |
| Thomas Duffy | Son | — | 11 | ~1919 |
Census Appearances
1910
Merrimack, New …
Son, age
Merrimack, New Hampshire · implied b. ~1910 — 5 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Duffy |
| Given Name | John G. |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 0 |
| Marital Status | Single |
| Birthplace | New Hampshire |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Birth State | New Hampshire |
| Birth Country | United States |
| Birthplace (normalized) | new hampshire |
1920
Merrimack, New …
Son, age 9
Merrimack, New Hampshire · implied b. ~1911 — 6 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Duffy |
| Given Name | John J. |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 9 |
| Marital Status | Single |
| Birthplace | New Hampshire |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Birth State | New Hampshire |
| Birth Country | United States |
| Birthplace (normalized) | new hampshire |
1930
Merrimack, New …
Son, age 20
Merrimack, New Hampshire · implied b. ~1910 — 6 household members
| Surname | Duffy |
| Given Name | John G |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 20 |
| Marital Status | Single |
| Birthplace | New Hampshire |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Occupation | Laborer |
| Industry | General Work |
| Class of Worker | W |
| Can Read/Write | Yes |
| Birth State | New Hampshire |
| Birth Country | United States |
| Birthplace (normalized) | new hampshire |
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 Duffy across 3 US Census years (1910, 1920 and 1930) in Merrimack, New Hampshire, using XGBoost record linkage. Identified parents: father Thomas Duffy (~0.92 confidence) and father Thomas Duffy (~0.92 confidence) and mother Annie Duffy (~0.92 confidence) and mother Annie Duffy (~0.92 confidence) and father Thomas Duffy (~0.92 confidence). The pedigree spans 1 generation with 5 identified ancestors.
Show:
Gen 1
Parents
confidence ≈ 0.92
Father
Thomas Duffy
b. ~1875
Source father
● Household
· direct · ~0.92
Father
Thomas Duffy
b. ~1875
Source father
● Household
· direct · ~0.92
Mother
Annie Duffy
b. ~1880
Source mother
● Household
· direct · ~0.92
Mother
Annie Duffy
b. ~1884
Source mother
● Household
· direct · ~0.92
Father
Thomas Duffy
b. ~1885
Source father
● Household
· direct · ~0.92
This person
Anchor record
John Duffy
Son · 1930 · age 20 · b. ~1910 · New Hampshire
★ You are viewing this record
Sibling
Katherine Duffy
Sibling · 1930 · age 23
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Martin Duffy
Sibling · 1930 · age 22
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Thomas Duffy
Sibling · 1930 · age 11
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 — Merrimack, New Hampshire
Open full size
1930 US Federal Census — Merrimack, New Hampshire
Page Contents
50 people indexed on this census page (ia:1930:15thcensus1304unit:0634)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 51 | Murdock A Buchanan | 43 | Son | — | New Hampshire |
| 52 | Ethel M Buchanan | 28 | Sister-in-law | — | Canada English |
| 53 | Olive F Buchanan | 23 | Sister-in-law | — | Canada English |
| 54 | Joseph P Melia | 48 | Head | Stock Clerk | Ireland |
| 55 | Nellie L Melia | 42 | Wife-H | — | New Hampshire |
| 56 | Mary H Melia | 13 | Daughter | — | New Hampshire |
| 57 | John J Melia | 11 | Son | — | New Hampshire |
| 58 | Eileen E Melia | 7 | Daughter | — | New Hampshire |
| 59 | Francis A Melia | 5 | Daughter | — | New Hampshire |
| 60 | Nellie A Farrell | 74 | Mother-in-law | — | New Hampshire |
| 61 | John J Maloney | 64 | Head | Passenger Conductor | Ireland |
| 62 | Catherine E Maloney | 55 | Wife-H | — | Ireland |
| 63 | James M Maloney | 31 | Son | Clerk | New Hampshire |
| 64 | Matthew F Maloney | 30 | Son | Pipe Fitter | New Hampshire |
| 65 | John H Maloney | 26 | Son | Plumber | New Hampshire |
| 66 | Diana M Maloney | 22 | Daughter-in-law | — | New Hampshire |
| 67 | Katherine A Jewell | 22 | Daughter | Sales Lady | New Hampshire |
| 68 | Benjamin Jewell | 22 | Son-in-law | Laborer | New Hampshire |
| 69 | Patricia A Jewell | 3 | Granddaughter | — | New Hampshire |
| 70 | Joseph M Callahan | 30 | Head | Polisher | Vermont |
| 71 | Mary M Callahan | 29 | Wife-H | — | New Hampshire |
| 72 | Joseph T Callahan | 8 | Son | — | New Hampshire |
| 73 | Francis A Callahan | 5 | Son | — | New Hampshire |
| 74 | Kathleen Callahan | 3 | Daughter | — | New Hampshire |
| 75 | Mary M Callahan | 1 | Daughter | — | New Hampshire |
| 76 | Thomas J Duffy | 45 | Head | Finisher | Ireland |
| 77 | Agnes F Duffy | 44 | Wife-H | — | Ireland |
| 78 | Katherine J Duffy | 23 | Daughter | — | New Hampshire |
| 79 | Martin H Duffy | 22 | Son | Pressman | New Hampshire |
| 80 | John G Duffy THIS PERSON | 20 | Son | Laborer | New Hampshire |
| 81 | Thomas Jr Duffy | 11 | Son | — | New Hampshire |
| 82 | Leo F Roche | 41 | Head | Book-Binder | Massachusetts |
| 83 | Ethel G Roche | 34 | Wife | — | Massachusetts |
| 84 | Leo F Jr Roche | 4 | Son | — | New Hampshire |
| 85 | Paul D Roche | 2 | Son | — | New Hampshire |
| 86 | James J Burke | 41 | Head | Electrotype Finisher | Massachusetts |
| 87 | Mary A Burke | 39 | Wife-H | — | Massachusetts |
| 88 | James J Jr Burke | 14 | Son | — | Massachusetts |
| 89 | Leo P Burke | 8 | Son | — | Massachusetts |
| 90 | Charles Burke | 7 | Son | — | Massachusetts |
| 91 | John Burke | 4 | Son | — | Massachusetts |
| 92 | William B Mcinnis | 49 | Head | Proprietor | Canada English |
| 93 | Emma H Mcinnis | 47 | Wife-H | — | New Hampshire |
| 94 | Katherine Mcinnis | 19 | Daughter | — | New Hampshire |
| 95 | Philip D Mcinnis | 14 | Son | — | New Hampshire |
| 96 | Henry A Runnell | 79 | Head | — | New Hampshire |
| 97 | Clara B Runnell | 71 | Wife-H | — | New York |
| 98 | Michael H Mulligan | 45 | Head | Salesman | New Hampshire |
| 99 | Alice G Mulligan | 45 | Wife-H | — | New Hampshire |
| 100 | Mary A Mulligan | 20 | Daughter | Stenographer | New Hampshire |
Pedigree Summary
John + 3 siblings
Gen 1 · 5 parents
~0.92
Max depth 4 (1900–1950 window)
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)