These research notes are provided as-is and contain supplementary working research.
Analysis
Two realistic end-states for the estimate and three levers that would move it
Two end-states are realistic for the parentage estimate. A marriage record for John and Mary in the Rivett-orbit parishes around East Dereham, or a kinsman's mention of a Gurney beyond the seas in one of the unread Norfolk family wills of the 1650s, would lift the identification from probable to highly probable, near eighty-five to ninety percent. Failing that, continued negative searching leaves it a permanently caveated best identification in the sixty-five to seventy percent band. Three levers carry most of the remaining value: Norfolk parish and probate images in the Rivett orbit, a professional examination of the East Dereham register, and a Y-DNA test of the discriminating English-line kit. The fact sheet now matches the case file's about-sixty-five-percent estimate; the figure remains a caveated synthesis of indirect evidence, not a substitute for the missing direct record.
Why this conclusion
- Depends on Open question Open question: untested Y-DNA discriminator (R1b-DF19)The untested discriminating Y-DNA kit is another of the three named levers.
- Depends on Open question Open: Entry E awaits professional examination of the original registerA professional reading of the East Dereham register is one of the three named levers.
- Synthesizes Analysis The unknown-corridor residual: eliminating named households does not clear the record's gapsThe residual space is what a Norfolk marriage record or kin-mention would have to shrink.
- Depends on Analysis What the identification rests on, and the four offsets that hold it below certaintyThe current estimate is the weighing of the four supports against the four offsets carried in the Candidate B unit.
Qualifications and conflicts
- Qualifies Identity hypothesis Candidate B: John was probably the son of Francis Gurney and Margaret RybettSets the bounds within which the parentage estimate can still move, and names what would move it.
- Qualifies Analysis The identification is reached by elimination and circumstantial fit, and predicts its own thin recordBounds the identification stated in the assessment: how far it can rise, and where it plateaus.
- Qualified by Negative result The English probate courts and Norfolk parish/marriage indexes, searched for any record naming the emigrant, his father Francis, or his family, return no positive match. No Francis Gurney G14 will survives in the Commissary, Archdeaconry, Prerogative, or Norwich courts; the two Rattlesden Rivett wills name no Margaret and no Gurney; and the Norfolk parish and same-name indexes yield no John-son-of-Francis baptism and no matching household for John or his wife Mary.The completed probate and Norfolk-index negatives reduce the remaining value of further searching to the specific named levers rather than an open-ended expectation that ordinary indexed records will solve the case.
Appears in
- John Gurney fact sheet — Fact-sheet note 8 states the parentage at "roughly a sixty percent probability" - the published estimate this item records as lagging the case file's current ~65%.
- John Gurney identity case file — Case file section 11 carries the ~65% estimate for Candidate B and the residual model it is read against.
Topic file location: Identity — assessment
Technical details
- Research item:
G13-RI-000178 - Graph revision:
244 - Machine-readable JSON:
/assets/g13-graph/findings/G13-RI-000178.json
This is one research item from the John Gurney research graph; the fuller narrative treatment is in the linked topic above and the research library.