MF
Mary Frederick — 1930 US Census Record
Linked across censuses1930 United States Federal Census · St Marys, Maryland
Our Model Tree links this Mary Frederick across the 1920 and 1930 US Censuses in St Marys, Maryland (XGBoost, ~Confirmed) — first a daughter (b.~1916), then head of a 10-person household.
Age 14
b. ~1916
Female
Daughter
Born: Maryland
Single
1930 Census Record Details
| Census Year | 1930 |
| Location | St Marys, Maryland |
| Surname | Frederick |
| Given Name | Mary N. |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | Black |
| Age | 14 |
| Marital Status | Single |
| Birthplace | Maryland |
| Father's Birthplace | Maryland |
| Mother's Birthplace | Maryland |
| Additional Details | |
| Can Read/Write | Yes |
| Birth State | Maryland |
| Birth Country | United States |
| Birthplace (normalized) | maryland |
| Township / Ward | Election District 6 |
| 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.
10 people recorded at the same address in the 1930 census.
| Name | Relation to head | Relative to Mary | Age | Birth yr |
|---|---|---|---|---|
| Regina Frederick | Daughter | — | 1 | ~1929 |
| Philip Frederick | Head | — | 48 | ~1882 |
| Joseph Frederick | Son | — | 6 | ~1924 |
| John Frederick | Son | — | 9 | ~1921 |
| Catherine Frederick | Spouse | — | 40 | ~1890 |
| Herman Frederick | Son | — | 19 | ~1911 |
| Alberta Frederick | Daughter | — | 11 | ~1919 |
| Julius Frederick | Son | — | 4 | ~1926 |
| James Frederick | Son | — | 16 | ~1914 |
| Mary Frederick | Daughter | — | 14 | ~1916 |
Census Appearances
1920
Charles, Maryland
Daughter, age 4
Charles, Maryland · implied b. ~1916 — 8 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Frederick |
| Given Name | Mary M. O. |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | Black |
| Age | 4 |
| Marital Status | Single |
| Birthplace | Maryland |
| Father's Birthplace | Maryland |
| Mother's Birthplace | Maryland |
| Speaks English | Yes |
| Birth State | Maryland |
| Birth Country | United States |
| Birthplace (normalized) | maryland |
1930
St Marys, …
Daughter, age 14
St Marys, Maryland · implied b. ~1916 — 10 household members
| Surname | Frederick |
| Given Name | Mary N. |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | Black |
| Age | 14 |
| Marital Status | Single |
| Birthplace | Maryland |
| Father's Birthplace | Maryland |
| Mother's Birthplace | Maryland |
| Can Read/Write | Yes |
| Birth State | Maryland |
| Birth Country | United States |
| Birthplace (normalized) | maryland |
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 Frederick across 2 US Census years (1920 and 1930) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
Mary Frederick
Daughter · 1930 · age 14 · b. ~1916 · Maryland
★ You are viewing this record
Sibling
James Frederick
Sibling · 1930 · age 16
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Joseph Frederick
Sibling · 1930 · age 6
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Alberta Frederick
Sibling · 1930 · age 11
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Julius Frederick
Sibling · 1930 · age 4
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Herman Frederick
Sibling · 1930 · age 19
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Regina Frederick
Sibling · 1930 · age 1
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
John Frederick
Sibling · 1930 · age 9
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
1930 US Federal Census — St Marys, Maryland
Open full size
1930 US Federal Census — St Marys, Maryland
Page Contents
50 people indexed on this census page (ia:1930:15thcensus879unit:0232)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 51 | Daughter Margret | 10 | Daughter | — | Maryland |
| 52 | Herbert Margret | 8 | Son | — | Maryland |
| 53 | John Margret | 6 | Son | — | Maryland |
| 54 | Joseph Margret | 5 | Son | — | Maryland |
| 55 | Edward Margret | 2 | Son | — | Maryland |
| 56 | Philip Frederick | 48 | Head | Laborer | Maryland |
| 57 | Catherine Frederick | 40 | Wife | — | Maryland |
| 58 | Herman Frederick | 19 | Son | Laborer | Maryland |
| 59 | James Frederick | 16 | Son | Laborer | Maryland |
| 60 | Mary N. Frederick THIS PERSON | 14 | Daughter | — | Maryland |
| 61 | Alberta Frederick | 11 | Daughter | — | Maryland |
| 62 | John Frederick | 9 | Son | — | Maryland |
| 63 | Joseph Frederick | 6 | Son | — | Maryland |
| 64 | Julius Frederick | 4 | Son | — | Maryland |
| 65 | Regina Frederick | 1 | Daughter | — | Maryland |
| 66 | William F. Nolan | 25 | Head | Laborer | Maryland |
| 67 | Leona M. Nolan | 22 | Wife | — | Maryland |
| 68 | Elsie V. Nolan | 4 | Daughter | — | Maryland |
| 69 | William F. Jr. Nolan | 2 | Son | — | Maryland |
| 70 | Mary E. Nolan | 0 | Daughter | — | Maryland |
| 71 | William Stevens | 69 | Head | Laborer | Maryland |
| 72 | Lucy Stevens | 50 | Wife | Laundress | Maryland |
| 73 | Roger H. Dean | 30 | Head | Farmer | Maryland |
| 74 | Gladys B. Dean | 30 | Wife | — | Maryland |
| 75 | Russell C. Dean | 6 | Son | — | Maryland |
| 76 | Frances R. Dean | 5 | Son | — | Maryland |
| 77 | Lola M. Dean | 2 | Daughter | — | Maryland |
| 78 | Emma F. Dean | 66 | Head | — | Maryland |
| 79 | Willard C. Dean | 21 | Son | Helper | Maryland |
| 80 | John H. Fenwick | 59 | Head | Farmer | Maryland |
| 81 | Blanche V. Fenwick | 52 | Wife | — | Maryland |
| 82 | Joseph G. Fenwick | 14 | Son | Helper | Maryland |
| 83 | Blanche G. Fenwick | 12 | Daughter | — | Maryland |
| 84 | Alice S. Fenwick | 10 | Daughter | — | Maryland |
| 85 | Milton S. Stephens | 25 | Head | Laborer | Maryland |
| 86 | Evelyn B. Stephens | 22 | Wife | — | Maryland |
| 87 | Agnes S. Stephens | 3 | Daughter | — | Maryland |
| 88 | Joseph M. Stephens | 2 | Son | — | Maryland |
| 89 | George C. Thompson | 59 | Head | Farmer | Maryland |
| 90 | Mary A. Thompson | 50 | Wife | — | Maryland |
| 91 | William Thompson | 17 | Son | Helper | Maryland |
| 92 | Hope A. Thompson | 14 | Daughter | — | Maryland |
| 93 | Samuel C. Thompson | 13 | Son | — | Maryland |
| 94 | Francis X. Spalding | 28 | Head | Farmer | Maryland |
| 95 | Elizabeth Spalding | 23 | Wife | — | Maryland |
| 96 | Catherine Spalding | 3 | Daughter | — | Maryland |
| 97 | Francis X. Jr. Spalding | 2 | Son | — | Maryland |
| 98 | Elizabeth Spalding | 1 | Daughter | — | Maryland |
| 99 | James C. Spalding | 0 | Son | — | Maryland |
| 100 | James Nolan | 78 | Head | Day Laborer | Maryland |
About This Record & Model Tree
This record was independently indexed by YourRoots from the 1930 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)