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.~1914), then head of a 7-person household.
Age 26
b. ~1914
Female
Daughter
Born: Kansas
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 | 26 |
| Marital Status | Single |
| Birthplace | Kansas |
| 1935 Residence (City) | Colfax twp |
| 1935 Residence (County) | Marion |
| Additional Details | |
| Occupation | House Keeper |
| Industry | Private Home |
| Class of Worker | NP |
| Highest Grade | Hs 4 |
| 1935 Residence | Same place |
| Birth State | Kansas |
| Birth Country | United States |
| Birthplace (normalized) | kansas |
| Occupation | Housekeeper |
| Township / Ward | Colfax Twp |
| Est. Birth Year | ~1914 |
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.
7 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to Mary | Age | Birth yr |
|---|---|---|---|---|
| Rachel Koch | Daughter | — | 17 | ~1923 |
| Lena Koch | Spouse | — | 58 | ~1882 |
| Mary Koch | Daughter | — | 26 | ~1914 |
| George Koch | Head | — | 53 | ~1887 |
| Ruben Koch | Son | — | 24 | ~1916 |
| Adam Koch | Other | — | 51 | ~1889 |
| Schnell Koch | Other | — | 35 | ~1905 |
Census Appearances
1930
Marion, Kansas
Daughter, age 16
Marion, Kansas · implied b. ~1914 — 5 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Koch |
| Given Name | Mary |
| Relationship to Head | daughter |
| Sex | F |
| Color / Race | White |
| Age | 16 |
| Marital Status | Single |
| Birthplace | Kansas |
| Age at First Marriage | 16 |
| Father's Birthplace | Russia |
| Mother's Birthplace | Russia |
| Occupation | none |
| Can Read/Write | Yes |
| Birth State | Kansas |
| Birth Country | United States |
| Birthplace (normalized) | kansas |
1940
Marion-County, Kansas
Daughter, age 26
Marion-County, Kansas · implied b. ~1914 — 7 household members
| Surname | Koch |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 26 |
| Marital Status | Single |
| Birthplace | Kansas |
| 1935 Residence (City) | Colfax twp |
| 1935 Residence (County) | Marion |
| Occupation | House Keeper |
| Industry | Private Home |
| Class of Worker | NP |
| Highest Grade | Hs 4 |
| 1935 Residence | Same place |
| Birth State | Kansas |
| Birth Country | United States |
| Birthplace (normalized) | kansas |
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 26 · b. ~1914 · Kansas
★ You are viewing this record
Sibling
Ruben Koch
Sibling · 1940 · age 24
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Rachel Koch
Sibling · 1940 · age 17
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-t0627-01244-00100)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | David E Gersal | 38 | Head | Farmer | South America |
| 2 | Mary Gersal | 36 | Wife | — | South America |
| 3 | Ruby J Gersal | 15 | Daughter | — | Kansas |
| 4 | Allen N Gersal | 12 | Son | — | Kansas |
| 5 | Delford D Gersal | 3 | Son | — | Kansas |
| 6 | Peter Bader | 28 | Head | Farmer | Kansas |
| 7 | Hanna Bader | 25 | Wife | — | Wisconsin |
| 8 | Gerald D Bader | 5 | Son | — | Kansas |
| 9 | James P Bader | 2 | Son | — | Kansas |
| 10 | Daniel Bader | 28 | Lodger | Farm Hand | Kansas |
| 11 | George Koch | 53 | Head | Farmer | Russia |
| 12 | Lena Koch | 58 | Wife | — | Russia |
| 13 | Mary Koch THIS PERSON | 26 | Daughter | House Keeper | Kansas |
| 14 | Ruben Koch | 24 | Son | Farmer | Kansas |
| 15 | Rachel Koch | 17 | Daughter | — | Kansas |
| 16 | Schnell John Koch | 35 | Son-in-law | — | Russia |
| 17 | Adam Koch | 51 | Brother | — | Russia |
| 18 | William O Piper | 43 | Head | Rock Crusher | Kansas |
| 19 | Gala E Piper | 40 | Wife | — | Nebraska |
| 20 | Bernard H Piper | 20 | Son | Laborer | Kansas |
| 21 | Bernadine H Piper | 18 | Daughter | General Housework | Kansas |
| 22 | Louise G Piper | 15 | Daughter | — | Nebraska |
| 23 | Billy J Piper | 14 | Son | — | Nebraska |
| 24 | Bobby D Piper | 9 | Son | — | Nebraska |
| 25 | Joan R Piper | 8 | Daughter | — | Kansas |
| 26 | Donald E Piper | 4 | Son | — | Kansas |
| 27 | Henry Weber | 66 | Head | Farmer | Kansas |
| 28 | Augusta Weber | 62 | Wife | — | Kansas |
| 29 | Edna E Weber | 25 | Daughter | — | Kansas |
| 30 | Harry H Bernhardt | 44 | Head | Farmer | Russia |
| 31 | Melinda Bernhardt | 37 | Wife | — | Kansas |
| 32 | Chester W Bernhardt | 18 | Son | — | Kansas |
| 33 | Kloris A Bernhardt | 17 | Daughter | — | Kansas |
| 34 | Ora J Bernhardt | 14 | Daughter | — | Kansas |
| 35 | Ruth M Bernhardt | 11 | Daughter | — | Kansas |
| 36 | Rosalee L Bernhardt | 9 | Daughter | — | Kansas |
| 37 | Daryl T Bernhardt | 8 | Son | — | Kansas |
| 38 | Stanley R Bernhardt | 6 | Son | — | Kansas |
| 39 | Duane G Bernhardt | 5 | Son | — | Kansas |
| 40 | David L Bernhardt | 1 | 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)