MK
Mary Kozlowski — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Hudson-County, New Jersey
Our Model Tree links this Mary Kozlowski across the 1930 and 1940 US Censuses in Hudson-County, New Jersey (XGBoost, ~Confirmed) — first a daughter (b.~1921), then head of a 5-person household.
Age 19
b. ~1921
Female
Daughter
Born: New Jersey
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Hudson-County, New Jersey |
| Surname | Kozlowski |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 19 |
| Marital Status | Single |
| Birthplace | New Jersey |
| 1935 Residence (City) | Weehawken Town |
| 1935 Residence (County) | Hudson |
| Additional Details | |
| Occupation | Waitress |
| Industry | Sandwich Shop |
| Class of Worker | PW |
| Hours Worked | 30 |
| Income (1939) | 308 |
| Highest Grade | Hs 2 |
| 1935 Residence | Same place |
| Birth State | New Jersey |
| Birth Country | United States |
| Birthplace (normalized) | new jersey |
| Occupation | Waitress |
| Township / Ward | Weehawken Town |
| Est. Birth Year | ~1921 |
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 Mary | Age | Birth yr |
|---|---|---|---|---|
| Irene Kozlowski | Daughter | — | 12 | ~1928 |
| Audrey Kozlowski | Daughter | — | 10 | ~1930 |
| Mary Kozlowski | Daughter | — | 19 | ~1921 |
| Mary Kozlowski | Spouse | — | 42 | ~1898 |
| Constantin Kozlowski | Head | — | 56 | ~1884 |
Census Appearances
1930
Bergen, New …
Daughter, age 8
Bergen, New Jersey · implied b. ~1922 — 9 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Kozlowski |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 8 |
| Marital Status | Single |
| Birthplace | New Jersey |
| Father's Birthplace | Poland |
| Mother's Birthplace | Poland |
| Occupation | none |
| Can Read/Write | Yes |
| Birth State | New Jersey |
| Birth Country | United States |
| Birthplace (normalized) | new jersey |
1940
Hudson-County, New …
Daughter, age 19
Hudson-County, New Jersey · implied b. ~1921 — 5 household members
| Surname | Kozlowski |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 19 |
| Marital Status | Single |
| Birthplace | New Jersey |
| 1935 Residence (City) | Weehawken Town |
| 1935 Residence (County) | Hudson |
| Occupation | Waitress |
| Industry | Sandwich Shop |
| Class of Worker | PW |
| Hours Worked | 30 |
| Income (1939) | 308 |
| Highest Grade | Hs 2 |
| 1935 Residence | Same place |
| 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 Kozlowski across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
Mary Kozlowski
Daughter · 1940 · age 19 · b. ~1921 · New Jersey
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Sibling
Irene Kozlowski
Sibling · 1940 · age 12
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Audrey Kozlowski
Sibling · 1940 · 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
1940 US Federal Census — Hudson-County, New Jersey
Open full size
1940 US Federal Census — Hudson-County, New Jersey
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-02353-01012)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Carmella Primavesi | 51 | Wife | — | Italy |
| 42 | Frank Primavesi | 25 | Son | Chauffeur | New Jersey |
| 43 | Joseph Jr. Primavesi | 17 | Son | Painter | New Jersey |
| 44 | Edward Primavesi | 9 | Son | — | New Jersey |
| 45 | William Emmer | 80 | Head | — | New York |
| 46 | Sarah Hunt | 63 | Head | — | New Jersey |
| 47 | Thomas Hunt | 32 | Son | Chauffeur | New York |
| 48 | James Hunt | 20 | Son | Welder | New Jersey |
| 49 | Joseph Woodward | 39 | Head | Marginal Clerk | New York |
| 50 | Helen Woodward | 44 | Wife | — | New Jersey |
| 51 | William Donnelly | 50 | Head | Fireman | New York |
| 52 | Anna Donnelly | 53 | Wife | — | New York |
| 53 | Anna Marie Donnelly | 16 | Daughter | — | New Jersey |
| 54 | Irene Nolden | 45 | Head | Typist | New Jersey |
| 55 | Dora Nolden | 41 | Sister | Inspector | New Jersey |
| 56 | Henry Nolden | 53 | Brother | Crossing Man | New York |
| 57 | Richard Nolden | 11 | Nephew | — | New Jersey |
| 58 | John Gruchalski | 32 | Head | Baker | Poland |
| 59 | Amelia Gruchalski | 36 | Wife | — | New Jersey |
| 60 | John Gruchalski | 8 | Son | — | New Jersey |
| 61 | Jacqueline Gruchalski | 0 | Daughter | — | New Jersey |
| 62 | Joseph Gruchalski | 60 | Head | Carpenter | Poland |
| 63 | Mary Gruchalski | 59 | Wife | — | Poland |
| 64 | Edward Gruchalski | 23 | Son | Chrome Plater | New Jersey |
| 65 | Chris Gruchalski | 21 | Son | Chrome Plater | New Jersey |
| 66 | Blank The Ends | None | 6 | — | — |
| 67 | Edward O'Donnell | 32 | Head | Painter | New Jersey |
| 68 | Dorothy O'Donnell | 25 | Wife | — | New Jersey |
| 69 | Edward O'Donnell | 6 | Son | — | New Jersey |
| 70 | Maureen O'Donnell | 1 | Daughter | — | New Jersey |
| 71 | Edward Mccue | 62 | Head | Laborer | New Jersey |
| 72 | Elizabeth Mccue | 55 | Wife | — | New Jersey |
| 73 | Edward Jr. Mccue | 35 | Son | Truck Driver | New Jersey |
| 74 | John Bruckmann | 53 | Head | Millwright | New Jersey |
| 75 | Constantin Kozlowski | 56 | Head | Storekeeper | Poland |
| 76 | Mary Kozlowski | 42 | Wife | — | Poland |
| 77 | Mary Kozlowski THIS PERSON | 19 | Daughter | Waitress | New Jersey |
| 78 | Irene Kozlowski | 12 | Daughter | — | New Jersey |
| 79 | Audrey Kozlowski | 10 | Daughter | — | New Jersey |
| 80 | Michael Kalczynski | 68 | Head | Store Keeper | Poland |
Related Census Records
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)