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Mary Mack — 1940 US Census Record
Model Tree available1940 United States Federal Census · Mercer-County, New Jersey
Our Model Tree links this Mary Mack across the 1920, 1930 and 1940 US Censuses in Mercer-County, New Jersey (XGBoost, ~Confirmed), with identified parents William & Charles — first a daughter (b.~1919), then head of a 4-person household.
Age 21
b. ~1919
Female
Daughter
Born: New Jersey
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Mercer-County, New Jersey |
| Surname | Mack |
| Given Name | Mary |
| Relationship to Head | daughter |
| Sex | F |
| Color / Race | White |
| Age | 21 |
| Marital Status | Single |
| Birthplace | New Jersey |
| 1935 Residence (City) | Princeton Borough |
| 1935 Residence (County) | Mercer |
| Additional Details | |
| Highest Grade | C 3 |
| 1935 Residence | Same place |
| Birth State | New Jersey |
| Birth Country | United States |
| Birthplace (normalized) | new jersey |
| Township / Ward | Princeton Borough |
| Est. Birth Year | ~1919 |
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 Mary | Age | Birth yr |
|---|---|---|---|---|
| Charles Mack | Head | — | 48 | ~1892 |
| Florence Mack | Daughter | — | 12 | ~1928 |
| Clara Mack | Spouse | — | 43 | ~1897 |
| Mary Mack | Daughter | — | 21 | ~1919 |
Census Appearances
1920
Mercer, New …
Daughter, age 1
Mercer, New Jersey · implied b. ~1919 — 3 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Mack |
| Given Name | Mary S. |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 1 |
| Marital Status | Single |
| Birthplace | New Jersey |
| Father's Birthplace | New Jersey |
| Mother's Birthplace | New Jersey |
| Birth State | New Jersey |
| Birth Country | United States |
| Birthplace (normalized) | new jersey |
1930
Mercer, New …
Daughter, age 11
Mercer, New Jersey · implied b. ~1919 — 9 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Mack |
| Given Name | Mary A. |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 11 |
| Marital Status | Single |
| Birthplace | New Jersey |
| Father's Birthplace | New Jersey |
| Mother's Birthplace | New Jersey |
| Occupation | none |
| Can Read/Write | Yes |
| Birth State | New Jersey |
| Birth Country | United States |
| Birthplace (normalized) | new jersey |
1940
Mercer-County, New …
Daughter, age 21
Mercer-County, New Jersey · implied b. ~1919 — 4 household members
| Surname | Mack |
| Given Name | Mary |
| Relationship to Head | daughter |
| Sex | F |
| Color / Race | White |
| Age | 21 |
| Marital Status | Single |
| Birthplace | New Jersey |
| 1935 Residence (City) | Princeton Borough |
| 1935 Residence (County) | Mercer |
| Highest Grade | C 3 |
| 1935 Residence | Same place |
| Birth State | New Jersey |
| Birth Country | United States |
| Birthplace (normalized) | new jersey |
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 Mack across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage. Identified parents: father William Covert (~0.92 confidence) and father Charles Mack (~0.92 confidence) and father Charles Mack (~0.92 confidence) and mother Clara Mack (~0.92 confidence) and mother Clara Mack (~0.92 confidence). The pedigree spans 1 generation with 5 identified ancestors.
Show:
Gen 1
Parents
confidence ≈ 0.92
Father
William Covert
b. ~1877
Source father
● Household
· direct · ~0.92
Father
Charles Mack
b. ~1892
Source father
● Household
· direct · ~0.92
Father
Charles Mack
b. ~1896
Source father
● Household
· direct · ~0.92
Mother
Clara Mack
b. ~1896
Source mother
● Household
· direct · ~0.92
Mother
Clara Mack
b. ~1897
Source mother
● Household
· direct · ~0.92
This person
Anchor record
Mary Mack
Daughter · 1940 · age 21 · b. ~1919 · New Jersey
★ You are viewing this record
Sibling
Florence Mack
Sibling · 1940 · age 12
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 — Mercer-County, New Jersey
Open full size
1940 US Federal Census — Mercer-County, New Jersey
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-02357-00571)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Gladys Sims | 42 | Head | Teacher | Iowa |
| 42 | Martha Sims | 13 | daughter | — | Iowa |
| 43 | Ella M. Gardner | 74 | Mother | — | Iowa |
| 44 | Charles Mcmullen | 56 | Head | Proprietor | New York |
| 45 | Katherine Mcmullen | 24 | daughter | — | New Jersey |
| 46 | Mary Mcmullen | 18 | daughter | Librarian | New Jersey |
| 47 | Charles Jr. Mcmullen | 13 | son | — | New Jersey |
| 48 | Henry C. Havenar | 72 | Head | — | New Jersey |
| 49 | Elizabeth S. Havenar | 65 | wife | — | New Jersey |
| 50 | Jean Spain | 30 | daughter | Library Assistant | New Jersey |
| 51 | Wallace Mershon | 54 | Head | Proprietor | New Jersey |
| 52 | Mary Mershon | 49 | wife | — | New Jersey |
| 53 | Margaret Mershon | 15 | daughter | — | New Jersey |
| 54 | Margaret Jewell | 79 | mother | — | New Jersey |
| 55 | James Denegher | 32 | Lodger | Taxi Driver | New York |
| 56 | Ted Butler Ronald | 40 | Head | Principal | Texas |
| 57 | Gertrude Ronald | 37 | Wife | — | Texas |
| 58 | Thelma Jean Ronald | 6 | daughter | — | New Jersey |
| 59 | Bertha Warren | 60 | Head | — | New York |
| 60 | Mary Greeble | 84 | mother | — | New Jersey |
| 61 | John S. Baumgartner | 40 | Head | Voice Teacher | Ohio |
| 62 | Ruth Baumgartner | 40 | wife | — | Ohio |
| 63 | Joanne Baumgartner | 9 | daughter | — | New York |
| 64 | Carolyn Baumgartner | 6 | daughter | — | New Jersey |
| 65 | Nancy Baumgartner | 4 | daughter | — | New Jersey |
| 66 | Charles H. Mack | 48 | Head | Stationary Engineer | New Jersey |
| 67 | Clara M. Mack | 43 | wife | — | New Jersey |
| 68 | Mary Mack THIS PERSON | 21 | daughter | — | New Jersey |
| 69 | Florence Mack | 12 | daughter | — | New Jersey |
| 70 | Frank Hoffman | 53 | Head | Music Teacher | Holland |
| 71 | Ann Hoffman | 53 | wife | — | Holland |
| 72 | John Hoffman | 23 | son | Choir Conductor | Dutch East Indies |
| 73 | Ilsa Hoffman | 21 | daughter | — | Dutch East Indies |
| 74 | George Courieur | 46 | Head | Music Teacher | France |
| 75 | Sarah Courieur | 47 | wife | Music Teacher | Belgium |
| 76 | Alice C. Stimson | 64 | Head | — | Ohio |
| 77 | Ruth S. Stimson | 28 | daughter | Grade Teacher | Ohio |
| 78 | Harry H. Morgan | 65 | Brother | Janitor | Ohio |
| 79 | Harry E. Hutchinson | 57 | Head | Treasurer | New Jersey |
| 80 | Marion M. Hutchinson | 52 | wife | — | New York |
Pedigree Summary
Mary + 1 sibling
Gen 1 · 5 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)