JK
John Kowalski — 1940 US Census Record
Model Tree available1940 United States Federal Census · Westchester-County, New York
Our Model Tree links this John Kowalski across the 1920, 1930 and 1940 US Censuses in Westchester-County, New York (XGBoost, ~Confirmed), with identified parents Julia & Charles — first a head (b.~1910), then head of a 4-person household.
Age 30
b. ~1910
Male
Head
Born: New York
Married
1940 Census Record Details
| Census Year | 1940 |
| Location | Westchester-County, New York |
| Surname | Kowalski |
| Given Name | John |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 30 |
| Marital Status | Married |
| Birthplace | New York |
| 1935 Residence (City) | Hastings on Hudson |
| 1935 Residence (County) | Westchester |
| Additional Details | |
| Occupation | Clerk |
| Industry | Retail Store |
| Class of Worker | PW |
| Hours Worked | 53 |
| Income (1939) | 1400 |
| Highest Grade | No 4 |
| 1935 Residence | Same place |
| Birth State | New York |
| Birth Country | United States |
| Birthplace (normalized) | new york |
| Occupation | Clerk |
| Township / Ward | Hastings On Hudson |
| 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.
4 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to John | Age | Birth yr |
|---|---|---|---|---|
| John Kowalski | Head | — | 30 | ~1910 |
| John Kowalski | Son | — | 3 | ~1937 |
| Eleanor Kowalski | Spouse | — | 23 | ~1917 |
| Joanne Kowalski | Daughter | — | 6 | ~1934 |
Census Appearances
1920
Westchester, New …
Son, age 11
Westchester, New York · implied b. ~1909 — 4 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Kowalski |
| Given Name | John |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 11 |
| Marital Status | Single |
| Birthplace | New York |
| Father's Birthplace | Poland |
| Mother's Birthplace | Poland |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Mother Tongue | Polish |
| Birth State | New York |
| Birth Country | United States |
| Birthplace (normalized) | new york |
1930
Westchester, New …
Son, age 20
Westchester, New York · implied b. ~1910 — 4 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Kowalski |
| Given Name | John |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 20 |
| Marital Status | Single |
| Birthplace | New York |
| Father's Birthplace | Poland |
| Mother's Birthplace | Poland |
| Occupation | Clerk |
| Industry | Lumber Yard |
| Class of Worker | W |
| Can Read/Write | Yes |
| Birth State | New York |
| Birth Country | United States |
| Birthplace (normalized) | new york |
1940
Westchester-County, New …
Head, age 30
Westchester-County, New York · implied b. ~1910 — 4 household members
| Surname | Kowalski |
| Given Name | John |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 30 |
| Marital Status | Married |
| Birthplace | New York |
| 1935 Residence (City) | Hastings on Hudson |
| 1935 Residence (County) | Westchester |
| Occupation | Clerk |
| Industry | Retail Store |
| Class of Worker | PW |
| Hours Worked | 53 |
| Income (1939) | 1400 |
| Highest Grade | No 4 |
| 1935 Residence | Same place |
| Birth State | New York |
| Birth Country | United States |
| Birthplace (normalized) | new york |
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 Kowalski across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage. Identified parents: mother Julia Kowalski (~0.92 confidence) and father Charles Kowalski (~0.92 confidence) and father Kostanty Kowalski (~0.92 confidence). The pedigree spans 1 generation with 3 identified ancestors.
Show:
Gen 1
Parents
confidence ≈ 0.92
Mother
Julia Kowalski
b. ~1876
Source mother
● Household
· direct · ~0.92
Father
Charles Kowalski
b. ~1878
Source father
● Household
· direct · ~0.92
Father
Kostanty Kowalski
b. ~1878
Source father
● Household
· direct · ~0.92
This person
Anchor record
John Kowalski
Head · 1940 · age 30 · b. ~1910 · New York
★ You are viewing this record
Confirmed / household (~0.90+)
Probable / derived (~0.65–0.89)
Candidate (<0.65, unverified)
Original Census Page
1940 US Federal Census — Westchester-County, New York
Open full size
1940 US Federal Census — Westchester-County, New York
Page Contents
27 people indexed on this census page (nara:1940:m-t0627-02803-00889)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Benjamin Filipovich | 17 | Son | Chauffeur | New York |
| 42 | William Lewis | 51 | Head | Chauffeur | New York |
| 43 | Mary Lewis | 50 | Wife | — | New York |
| 44 | Anthony Tasaio | 46 | Head | Pipe Man | New York |
| 45 | Catherine Tasaio | 45 | Wife | — | New York |
| 46 | Catherine Tasaio | 21 | Daughter | Clerking | New York |
| 47 | Stephen Tasaio | 19 | Son | — | New York |
| 48 | Cecilia Tasaio | 15 | Daughter | — | New York |
| 49 | Anna Tasaio | 12 | Daughter | — | New York |
| 50 | John Tasaio | 10 | Son | — | New York |
| 51 | Thos P Martin | 43 | Head | Electrical Instr | New York |
| 52 | Rosalie Martin | 39 | Sister | — | New York |
| 53 | Bridget R Martin | 75 | Aunt | — | New York |
| 54 | Chas Brennen | 30 | Head | Chauffeur | New York |
| 55 | Estelle Brennen | 30 | Wife | — | New York |
| 56 | Marie Brennen | 4 | Daughter | — | New York |
| 57 | George Carpentier | 43 | Head | Clerk | New York |
| 58 | Ruth Carpentier | 41 | Wife | — | New York |
| 59 | Geo Caddock | 36 | Head | Painter | England |
| 60 | John Kowalski THIS PERSON | 30 | Head | Clerk | New York |
| 61 | Eleanor Kowalski | 23 | Wife | — | New York |
| 62 | Joanne Kowalski | 6 | Daughter | — | New York |
| 63 | John Kowalski | 3 | Son | — | New York |
| 64 | Walter Devenish | 33 | Head | Laboratory Asst | New York |
| 65 | Emma Devenish | 33 | Wife | — | Lithuania |
| 66 | Gloria Devenish | 9 | Daughter | — | New York |
| 67 | Betty Devenish | 2 | Daughter | — | New York |
Pedigree Summary
John
Gen 1 · 3 parents
~0.92
Max depth 4 (1900–1950 window)
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)