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William Koch — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Washington-County, Oregon
Our Model Tree links this William Koch across the 1930 and 1940 US Censuses in Washington-County, Oregon (XGBoost, ~Confirmed) — first a head (b.~1884), then head of a 9-person household.
Age 56
b. ~1884
Male
Head
Born: South Dakota
Married
1940 Census Record Details
| Census Year | 1940 |
| Location | Washington-County, Oregon |
| Surname | Koch |
| Given Name | William A D |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 56 |
| Marital Status | Married |
| Birthplace | South Dakota |
| 1935 Residence (City) | R |
| 1935 Residence (County) | Washington |
| Additional Details | |
| Occupation | Farmer |
| Industry | Farm |
| Class of Worker | OA |
| Hours Worked | 30 |
| Income (1939) | 0 |
| Highest Grade | C-3 |
| 1935 Residence | Oregon |
| Birth State | South Dakota |
| Birth Country | United States |
| Birthplace (normalized) | south dakota |
| Occupation | Farmer |
| Township / Ward | Precinct 9 |
| Est. Birth Year | ~1884 |
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.
9 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to William | Age | Birth yr |
|---|---|---|---|---|
| Shirley Koch | Daughter | — | 22 | ~1918 |
| Patricia Swanson | Daughter | — | 5 | ~1935 |
| Fred Schell | Son | — | 5 | ~1935 |
| Alma Koch | Spouse | — | 52 | ~1888 |
| William Koch | Head | — | 56 | ~1884 |
| Larry Swanson | Son | — | 1 | ~1939 |
| Doris Koch | Daughter | — | 20 | ~1920 |
| Donald Swanson | Son | — | 19 | ~1921 |
| Betty Schell | Daughter | — | 8 | ~1932 |
Census Appearances
1930
Washington, Oregon
Head, age 46
Washington, Oregon · implied b. ~1884 — 4 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Koch |
| Given Name | W. Albert |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 46 |
| Marital Status | Married |
| Birthplace | South Dakota |
| Age at First Marriage | 25 |
| Father's Birthplace | Germany |
| Mother's Birthplace | Germany |
| Occupation | Farmer |
| Industry | Gen Farm |
| Class of Worker | VVV |
| Can Read/Write | Yes |
| Home Owned/Rented | O |
| Home Value / Rent | 15,000 |
| Birth State | South Dakota |
| Birth Country | United States |
| Birthplace (normalized) | south dakota |
1940
Washington-County, Oregon
Head, age 56
Washington-County, Oregon · implied b. ~1884 — 9 household members
| Surname | Koch |
| Given Name | William A D |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 56 |
| Marital Status | Married |
| Birthplace | South Dakota |
| 1935 Residence (City) | R |
| 1935 Residence (County) | Washington |
| Occupation | Farmer |
| Industry | Farm |
| Class of Worker | OA |
| Hours Worked | 30 |
| Income (1939) | 0 |
| Highest Grade | C-3 |
| 1935 Residence | Oregon |
| Birth State | South Dakota |
| Birth Country | United States |
| Birthplace (normalized) | south dakota |
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 William Koch across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
William Koch
Head · 1940 · age 56 · b. ~1884 · Oregon
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Confirmed / household (~0.90+)
Probable / derived (~0.65–0.89)
Candidate (<0.65, unverified)
Original Census Page
1940 US Federal Census — Washington-County, Oregon
Open full size
1940 US Federal Census — Washington-County, Oregon
Page Contents
28 people indexed on this census page (nara:1940:m-t0627-03382-00263)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Royda Egberg | 27 | Head | Brakeman | Oregon |
| 42 | Winifred L Egberg | 21 | Wife | Stenographer | Oregon |
| 43 | William G Armstrong | 29 | Lodger | Sheet Metal Worker | Washington |
| 44 | Ferdinand A Schilling | 70 | Head | — | Germany |
| 45 | John Garica | 64 | Head | — | Russia |
| 46 | Virgil L Conklin | 54 | Head | Woodcutter | Ohio |
| 47 | Esther A Conklin | 52 | Wife | — | Ohio |
| 48 | Edwin L Conklin | 20 | Son | Trimmerman | Ohio |
| 49 | William A D Koch THIS PERSON | 56 | Head | Farmer | South Dakota |
| 50 | Alma P Koch | 52 | Wife | — | Minnesota |
| 51 | Shirley L Koch | 22 | Daughter | Housekeeper | Minnesota |
| 52 | Doris A Koch | 20 | Daughter | — | Minnesota |
| 53 | Donald K Swanson | 19 | Son | Asst Educational Advisor | Washington |
| 54 | Patricia Swanson | 5 | Daughter | — | Oregon |
| 55 | Larry G Swanson | 1 | Son | — | Oregon |
| 56 | Betty M Schell | 8 | Daughter | — | North Dakota |
| 57 | Fred J Schell | 5 | Son | — | North Dakota |
| 58 | Reuel B D Doughty | 70 | Head | Farmer | Iowa |
| 59 | Maggie A Doughty | None | Wife | — | — |
| 60 | Woodrow W Woodbridge | 48 | Head | — | South Carolina |
| 61 | Wilbert R D Riley | 42 | Head | Stage Driver | California |
| 62 | Myrtle Riley | 32 | Wife | — | Utah |
| 63 | Oliver R Taylor | 41 | Lodger | Stage Driver | Oregon |
| 64 | Geraldine M Taylor | 16 | Lodger | — | Oregon |
| 65 | E Hoon | 53 | Head | — | New York |
| 66 | Osval C Giletrap | 59 | Head | Linotype Opr | Kansas |
| 67 | Lura Giletrap | 54 | Wife | — | Oregon |
| 68 | Henry L Sorenson | 39 | Head | Officer | Denmark |
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)