MK
Mary Koch — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Marion-County, Kansas
Our Model Tree links this Mary Koch across the 1930 and 1940 US Censuses in Marion-County, Kansas (XGBoost, ~Confirmed) — first a daughter (b.~1916), then head of a 6-person household.
Age 24
b. ~1916
Female
Daughter
Born: Nebraska
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Marion-County, Kansas |
| Surname | Koch |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 24 |
| Marital Status | Single |
| Birthplace | Nebraska |
| 1935 Residence (City) | Clark Township |
| 1935 Residence (County) | Marion |
| Additional Details | |
| Occupation | housekeeper |
| Industry | Private home |
| Class of Worker | PW |
| Hours Worked | 40 |
| Income (1939) | 500 |
| Highest Grade | C 4 |
| 1935 Residence | Same house |
| Birth State | Nebraska |
| Birth Country | United States |
| Birthplace (normalized) | nebraska |
| Occupation | Housekeeper |
| Township / Ward | Clark Township |
| Est. Birth Year | ~1916 |
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 Mary | Age | Birth yr |
|---|---|---|---|---|
| Mary Koch | Daughter | — | 24 | ~1916 |
| Molly Koch | Daughter | — | 30 | ~1910 |
| Martha Koch | Daughter | — | 21 | ~1919 |
| Louis Koch | Head | — | 58 | ~1882 |
| Esther Koch | Daughter | — | 20 | ~1920 |
| Eva Koch | Spouse | — | 56 | ~1884 |
Census Appearances
1930
Marion, Kansas
Daughter, age 13
Marion, Kansas · implied b. ~1917 — 8 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Koch |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 13 |
| Marital Status | Single |
| Birthplace | Nebraska |
| Father's Birthplace | Russia |
| Mother's Birthplace | Russia |
| Can Read/Write | Yes |
| Birth State | Nebraska |
| Birth Country | United States |
| Birthplace (normalized) | nebraska |
1940
Marion-County, Kansas
Daughter, age 24
Marion-County, Kansas · implied b. ~1916 — 6 household members
| Surname | Koch |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 24 |
| Marital Status | Single |
| Birthplace | Nebraska |
| 1935 Residence (City) | Clark Township |
| 1935 Residence (County) | Marion |
| Occupation | housekeeper |
| Industry | Private home |
| Class of Worker | PW |
| Hours Worked | 40 |
| Income (1939) | 500 |
| Highest Grade | C 4 |
| 1935 Residence | Same house |
| Birth State | Nebraska |
| Birth Country | United States |
| Birthplace (normalized) | nebraska |
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 Koch across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
Mary Koch
Daughter · 1940 · age 24 · b. ~1916 · Kansas
★ You are viewing this record
Sibling
Molly Koch
Sibling · 1940 · age 30
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Martha Koch
Sibling · 1940 · age 21
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Esther Koch
Sibling · 1940 · age 20
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 — Marion-County, Kansas
Open full size
1940 US Federal Census — Marion-County, Kansas
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-01244-00061)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Jerome Zajicman | 11 | Son | — | Kansas |
| 42 | Maxine Zajicman | 5 | Daughter | — | Kansas |
| 43 | Louis Koch | 58 | Head | Farmer | Russia |
| 44 | Eva Koch | 56 | Wife | — | Russia |
| 45 | Molly Koch | 30 | Daughter | Housekeeper | Russia |
| 46 | Mary Koch THIS PERSON | 24 | Daughter | Housekeeper | Nebraska |
| 47 | Martha Koch | 21 | Daughter | — | Nebraska |
| 48 | Esther Koch | 20 | Daughter | Housekeeper | Kansas |
| 49 | John Koch | 32 | Head | Farmer | Kansas |
| 50 | Elizabeth Koch | 28 | Wife | — | Nebraska |
| 51 | Shirley Dorn | 8 | Step-Daughter | — | Nebraska |
| 52 | Joseph F. Vinduska | 60 | Head | Farmer | Kansas |
| 53 | Cecelia Vinduska | 60 | Wife | — | Kansas |
| 54 | Anton Vinduska | 32 | Son | — | Kansas |
| 55 | Frances Vinduska | 26 | Daughter | — | Kansas |
| 56 | Louis Vinduska | 23 | Son | — | Kansas |
| 57 | Paul Vinduska | 21 | Son | — | Kansas |
| 58 | Gottfried Benhardt | 55 | Head | Farmer | Russia |
| 59 | Julia Benhardt | 52 | Wife | — | Russia |
| 60 | Mildred Benhardt | 22 | Daughter | — | Kansas |
| 61 | Theodore Benhardt | 20 | Son | — | Kansas |
| 62 | Leona Benhardt | 18 | Daughter | — | Kansas |
| 63 | Clement Klenda | 36 | Head | Farmer | Kansas |
| 64 | Emma Klenda | 31 | Wife | — | Kansas |
| 65 | Richard Klenda | 7 | Son | — | Kansas |
| 66 | Robert Klenda | 3 | Son | — | Kansas |
| 67 | Emil Zajicman | 42 | Head | Farmer | Kansas |
| 68 | Joshine Zajicman | 40 | Wife | — | Nebraska |
| 69 | John A. Zajicman | 32 | Head | Farmer | Kansas |
| 70 | Elizabeth Zajicman | 26 | Wife | — | Kansas |
| 71 | Shirley Zajicman | 2 | Daughter | — | Kansas |
| 72 | Anna Moravec | 82 | Head | — | Minnesota |
| 73 | Bessie Vinduska | 38 | Head | Operator | Kansas |
| 74 | Francis Vinduska | 83 | Mother | — | Czechoslovakia |
| 75 | Victoria Sexty | 45 | Neice | Assistant Operator | Kansas |
| 76 | Joe Melgung | 45 | Head | Farmer | Kansas |
| 77 | Mary Melgung | 38 | Wife | — | Nebraska |
| 78 | Bernard Melgung | 16 | Son | — | Kansas |
| 79 | Paul Melgung | 13 | Son | — | Kansas |
| 80 | Leon Melgung | 11 | Son | — | Kansas |
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)