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John Kozlowski — 1930 US Census Record
Linked across censuses1930 United States Federal Census · Allegheny, Pennsylvania
Our Model Tree links this John Kozlowski across the 1930 and 1940 US Censuses in Allegheny, Pennsylvania (XGBoost, ~Confirmed) — first a son (b.~1927), then head of a 10-person household.
Age 3
b. ~1927
Male
Son
Born: Pennsylvania
Single
1930 Census Record Details
| Census Year | 1930 |
| Location | Allegheny, Pennsylvania |
| Surname | Kozlowski |
| Given Name | John J |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 3 |
| Marital Status | Single |
| Birthplace | Pennsylvania |
| Father's Birthplace | Poland |
| Mother's Birthplace | Poland |
| Additional Details | |
| Birth State | Pennsylvania |
| Birth Country | United States |
| Birthplace (normalized) | pennsylvania |
| Township / Ward | City Of Pittsburgh |
| Est. Birth Year | ~1927 |
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 John | Age | Birth yr |
|---|---|---|---|---|
| Veronica Kozlowski | Other | — | 40 | ~1890 |
| Lottie Kozlowski | Daughter | — | 18 | ~1912 |
| John Kozlowski | Head | — | 42 | ~1888 |
| John Kozlowski | Son | — | 3 | ~1927 |
| Stanley Kozlowski | Son | — | 20 | ~1910 |
| Harry Kozlowski | Son | — | 9 | ~1921 |
| Edward Kozlowski | Son | — | 6 | ~1924 |
| Frank Kozlowski | Son | — | 16 | ~1914 |
| Marie Kozlowski | Daughter | — | 14 | ~1916 |
| Joseph Kozlowski | Son | — | 11 | ~1919 |
Census Appearances
1930
Allegheny, Pennsylvania
Son, age 3
Allegheny, Pennsylvania · implied b. ~1927 — 10 household members
| Surname | Kozlowski |
| Given Name | John J |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 3 |
| Marital Status | Single |
| Birthplace | Pennsylvania |
| Father's Birthplace | Poland |
| Mother's Birthplace | Poland |
| Birth State | Pennsylvania |
| Birth Country | United States |
| Birthplace (normalized) | pennsylvania |
1940
Allegheny-County, Pennsylvania
Son, age 13
Allegheny-County, Pennsylvania · implied b. ~1927 — 4 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Kozlowskiewicz |
| Given Name | John |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 13 |
| Marital Status | Single |
| Birthplace | Pennsylvania |
| 1935 Residence (City) | Pittsburgh |
| 1935 Residence (County) | Allegheny |
| Industry | 0 |
| Highest Grade | No 8 |
| 1935 Residence | Same place |
| Birth State | Pennsylvania |
| Birth Country | United States |
| Birthplace (normalized) | pennsylvania |
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 Kozlowski across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
John Kozlowski
Son · 1930 · age 3 · b. ~1927 · Pennsylvania
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Sibling
Lottie Kozlowski
Sibling · 1930 · age 18
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Stanley Kozlowski
Sibling · 1930 · age 20
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Joseph Kozlowski
Sibling · 1930 · age 11
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Harry Kozlowski
Sibling · 1930 · age 9
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Marie Kozlowski
Sibling · 1930 · age 14
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Edward Kozlowski
Sibling · 1930 · age 6
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Frank Kozlowski
Sibling · 1930 · age 16
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 — Allegheny, Pennsylvania
Open full size
1930 US Federal Census — Allegheny, Pennsylvania
Page Contents
50 people indexed on this census page (ia:1930:fifteenthcensus00reel1983:0476)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 51 | Marie A Novalk | 56 | Wife-H | — | Germany |
| 52 | Helen F Novalk | 25 | Daughter | — | Pennsylvania |
| 53 | Marie E Novalk | 17 | Daughter | Typist | Pennsylvania |
| 54 | Oswald A Stutchens | 30 | Head | Garage Keeper | Pennsylvania |
| 55 | Alice J Stutchens | 30 | Wife-H | Sales Lady | Pennsylvania |
| 56 | Arlene M Stutchens | 6 | Daughter | — | Pennsylvania |
| 57 | Donald L Stutchens | 4 | Son | — | Pennsylvania |
| 58 | Earl A Rose | 11 | Step son | — | Pennsylvania |
| 59 | Thomas Corboy | 43 | Head | Brake Hand | Pennsylvania |
| 60 | Bridget Corboy | 35 | Wife-H | — | Northern Ireland |
| 61 | Walter Wroblewski | 47 | Head | Roller | Poland |
| 62 | Josephine B Wroblewski | 38 | Wife-H | — | Pennsylvania |
| 63 | Stella J Wroblewski | 18 | Daughter | Stenographer | Pennsylvania |
| 64 | Joseph W Wroblewski | 16 | Son | — | Pennsylvania |
| 65 | Verna C Wroblewski | 13 | Daughter | — | Pennsylvania |
| 66 | Mary A Wroblewski | 11 | Daughter | — | Pennsylvania |
| 67 | John Kozlowski | 42 | Head | Roller | Poland |
| 68 | Veronica Kozlowski | 40 | Wife-H | — | Poland |
| 69 | Stanley J Kozlowski | 20 | Son | Gager | Pennsylvania |
| 70 | Lottie J Kozlowski | 18 | Daughter | Cracker | Pennsylvania |
| 71 | Frank S Kozlowski | 16 | Son | Roller | Pennsylvania |
| 72 | Marie G Kozlowski | 14 | Daughter | — | Pennsylvania |
| 73 | Joseph A Kozlowski | 11 | Son | — | Pennsylvania |
| 74 | Harry J Kozlowski | 9 | Son | — | Pennsylvania |
| 75 | Edward S Kozlowski | 6 | Son | — | Pennsylvania |
| 76 | John J Kozlowski THIS PERSON | 3 | Son | — | Pennsylvania |
| 77 | Walter Zukowski | 26 | Head | Gager | Pennsylvania |
| 78 | Mary J Zukowski | 23 | Wife-H | — | Pennsylvania |
| 79 | Stanley Kaminski | 47 | Head | Com Labour | Poland |
| 80 | Stella C Kaminski | 42 | Wife-H | — | Poland |
| 81 | Joseph Kaminski | 20 | Son | Gager | Pennsylvania |
| 82 | Sophie Kaminski | 17 | Daughter | Cracker | Pennsylvania |
| 83 | Anthony Kaminski | 15 | Son | — | Pennsylvania |
| 84 | John Kaminski | 11 | Son | — | Pennsylvania |
| 85 | Kathryn Kaminski | 8 | Daughter | — | Pennsylvania |
| 86 | Stanley Matella | 68 | Father-law | — | Poland |
| 87 | Frank Baron | 24 | Head | Mechanic | Pennsylvania |
| 88 | Violet M Baron | 25 | Wife-H | — | Pennsylvania |
| 89 | Edward J Baron | 3 | Son | — | Pennsylvania |
| 90 | Adam Dargowski | 41 | Head | Com Labour | Poland |
| 91 | Stella Dargowski | 34 | Wife-H | — | Poland |
| 92 | Joseph A Dargowski | 13 | Son | — | Pennsylvania |
| 93 | Frank A Dargowski | 12 | Son | — | Pennsylvania |
| 94 | Chester M Dargowski | 8 | Son | — | Pennsylvania |
| 95 | Irene Dargowski | 6 | Daughter | — | Pennsylvania |
| 96 | Mary E Dargowski | 4 | Daughter | — | Pennsylvania |
| 97 | Lillian Dargowski | 1 | Daughter | — | Pennsylvania |
| 98 | Jacob Puffer | 59 | Head | Com Labour | France |
| 99 | Cecelia A Puffer | 28 | Wife-H | — | Pennsylvania |
| 100 | Gilbert Puffer | 3 | Son | — | Pennsylvania |
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)