JK
John Kozlowski — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Schenectady-County, New York
Our Model Tree links this John Kozlowski across the 1930 and 1940 US Censuses in Schenectady-County, New York (XGBoost, ~Confirmed) — first a son (b.~1922), then head of a 6-person household.
Age 18
b. ~1922
Male
Son
Born: Poland
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Schenectady-County, New York |
| Surname | Kozlowski |
| Given Name | John |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 18 |
| Marital Status | Single |
| Birthplace | Poland |
| 1935 Residence (City) | Schenectady |
| 1935 Residence (County) | Schenectady |
| Naturalization Status | Alien |
| Additional Details | |
| Hours Worked | 0 |
| Income (1939) | 0 |
| Highest Grade | Hs 4 |
| 1935 Residence | Same Place |
| Birth Country | Poland |
| Birthplace (normalized) | poland |
| Township / Ward | Schenectady |
| Est. Birth Year | ~1922 |
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 1940 census.
| Name | Relation to head | Relative to John | Age | Birth yr |
|---|---|---|---|---|
| Hedwig Kozlowski | Daughter | — | 14 | ~1926 |
| Jane Kozlowski | Daughter | — | 12 | ~1928 |
| Mildred Kozlowski | Spouse | — | 40 | ~1900 |
| John Kozlowski | Son | — | 18 | ~1922 |
| Patricia Kozlowski | Daughter | — | 4 | ~1936 |
| Joseph Kozlowski | Head | — | 50 | ~1890 |
Census Appearances
1930
Schenectady, New …
Son, age 7
Schenectady, New York · implied b. ~1923 — 5 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | KOZLOWSKI |
| Given Name | JOHN |
| Relationship to Head | SON |
| Sex | M |
| Color / Race | White |
| Age | 7 |
| Marital Status | Single |
| Birthplace | POLAND |
| Naturalization Status | Alien |
| Year of Immigration | 1928 |
| Father's Birthplace | POLAND |
| Mother's Birthplace | POLAND |
| Occupation | NONE |
| Mother Tongue | POLISH |
| Birth Country | Poland |
| Birthplace (normalized) | poland |
1940
Schenectady-County, New …
Son, age 18
Schenectady-County, New York · implied b. ~1922 — 6 household members
| Surname | Kozlowski |
| Given Name | John |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 18 |
| Marital Status | Single |
| Birthplace | Poland |
| 1935 Residence (City) | Schenectady |
| 1935 Residence (County) | Schenectady |
| Naturalization Status | Alien |
| Hours Worked | 0 |
| Income (1939) | 0 |
| Highest Grade | Hs 4 |
| 1935 Residence | Same Place |
| Birth Country | Poland |
| Birthplace (normalized) | poland |
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 · 1940 · age 18 · b. ~1922 · New York
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Sibling
Hedwig Kozlowski
Sibling · 1940 · age 14
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Jane Kozlowski
Sibling · 1940 · age 12
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Patricia Kozlowski
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 — Schenectady-County, New York
Open full size
1940 US Federal Census — Schenectady-County, New York
Page Contents
39 people indexed on this census page (nara:1940:m-t0627-02777-00035)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Frederick Robert Frederick | 14 | Son | — | New York |
| 42 | Jack Frederick | 9 | Son | — | New York |
| 43 | Arthur Frederick | 5 | Son | — | New York |
| 44 | Anna Frederick | 5 | Daughter | — | New York |
| 45 | Anna Smith | 67 | Mother-in-law | — | New York |
| 46 | Isaac Smith | 35 | Brother-in-law | Laborer | New York |
| 47 | Joseph Pennell | 50 | Head | Laborer | France |
| 48 | Ella Mae Pennell | 40 | Wife | — | New York |
| 49 | Vivien Pennell | 13 | Daughter | — | New York |
| 50 | Marion Pennell | 11 | Daughter | — | New York |
| 51 | Joseph M Pennell | 8 | Son | — | New York |
| 52 | George Pennell | 7 | Son | — | New York |
| 53 | Leonard Pennell | 5 | Son | — | New York |
| 54 | Carl Pennell | 3 | Son | — | New York |
| 55 | Carrie Ann Pennell | 2 | Daughter | — | New York |
| 56 | Adam Swarczewski | 46 | Head | Proprietor | Poland |
| 57 | Jennie Swarczewski | 36 | Wife | — | New York |
| 58 | Walter Swarczewski | 19 | Son | — | New York |
| 59 | Clara Swarczewski | 13 | Daughter | — | New York |
| 60 | Edward Swarczewski | 5 | Son | — | New York |
| 61 | Stanley Lewandowski | 58 | Head | Blacksmith | Poland |
| 62 | Valeria Lewandowski | 56 | Wife | — | Poland |
| 63 | Joseph Puskasiewicz | 28 | Head | Laborer | Massachusetts |
| 64 | Virginia Puskasiewicz | 23 | Wife | — | New York |
| 65 | Janet Puskasiewicz | 4 | Daughter | — | New York |
| 66 | John Rutkowski | 27 | Head | Laborer | New York |
| 67 | Mary Rutkowski | 21 | Wife | — | Poland |
| 68 | Joseph Kozlowski | 50 | Head | Janitor | Poland |
| 69 | Mildred Kozlowski | 40 | Wife | — | New York |
| 70 | John Kozlowski THIS PERSON | 18 | Son | — | Poland |
| 71 | Hedwig Kozlowski | 14 | Daughter | — | Poland |
| 72 | Jane Kozlowski | 12 | Daughter | — | Poland |
| 73 | Patricia Kozlowski | 4 | Daughter | — | New York |
| 74 | John Winuk | 26 | Head | Mail Clerk | New York |
| 75 | Julia Winuk | 25 | Wife | — | New York |
| 76 | Mary Winuk | 4 | Daughter | — | New York |
| 77 | Peter Winuk | 3 | Son | — | New York |
| 78 | Betty Lou Winuk | 0 | Daughter | — | New York |
| 79 | Albert Rogalski | 60 | Head | — | Poland |
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)