Surname Distribution Analysis and One-Name Studies

What surname distribution can tell you

Surname distribution analysis answers questions you might not have thought to ask:

• Which families dominate your tree, and which are under-researched?
• Are your ancestors concentrated in one region, or scattered?
• Which spelling variants of the same name are you treating as separate families?
• Are there surname clusters that suggest endogamy (intermarriage within a community)?
• Which surnames give you the best chance of breaking through a brick wall via collateral research?

For researchers running a one-name study — tracing every bearer of a particular surname — this kind of analysis is the foundation of the entire project.

Counting surname frequency

GEDminer's Surname Filter (used in the People directory, Census Toolbox, and Vital Sharpener) ranks every surname in your tree by frequency. Open the People tab and look at the surname dropdown — names are sorted by how many individuals carry them.

The top three to five surnames are usually:

• Your direct paternal line (because surnames pass father-to-son in most Western traditions)
• The paternal line of a particularly well-researched maternal grandparent
• Common local surnames in the regions your family came from

If a surname you expect to be prominent is missing or low-ranked, that's a research priority — it usually means a branch is under-documented.

Handling surname variants

The same family often appears under multiple spellings:

• Smith / Smyth / Smythe
• Macdonald / MacDonald / McDonald
• O'Brien / OBrien / Obrien / Brien
• Schmidt / Schmitt / Schmid (after immigration)

GEDminer's Surname Variants feature (toggleable in Settings) clusters phonetically and visually similar names using Soundex and edit-distance matching with a 0.55 Levenshtein threshold. This means "Macdonald" and "McDonald" are recognised as the same family for analysis purposes.

For one-name studies you should additionally maintain a manual variants list documenting historical spellings found in records. Some 18th-century parish clerks spelled the same family three different ways in three consecutive baptisms.

Mapping geographic distribution

Combine surname filtering with the Locations tab and Migration Analysis to see where each surname clusters:

1. In the People tab, filter by a single surname
2. Switch to the Locations tab to see only places associated with that surname
3. Open Migration Analysis to see how that surname moved between regions over time

A surname concentrated in one parish for 200 years suggests an endogamous farming family. A surname that scatters across multiple counties in a single generation usually marks an industrial-era migration. A surname that crosses an ocean once and then stays put marks an emigration event worth investigating in passenger records.

Identifying brick-wall opportunities

Surname distribution analysis often reveals research opportunities you've been missing:

• Lone individuals: A surname with only one or two bearers in your tree usually means an under-researched in-law line. Their parents and siblings exist somewhere — find them.
• Geographic anomalies: A surname that appears in one unexpected location may indicate a previously unknown migration
• Frequency drops: A surname that disappears between two generations may mean an undocumented daughter-out marriage, an emigration, or a death cluster
• Variant gaps: If you have many "Smiths" but no "Smyths" in a region where both spellings were common, you may be missing records filed under the variant

For each anomaly, add a research task in your plan to investigate further.

Running a one-name study

If you want to formalise a one-name study (registering with the Guild of One-Name Studies or similar):

1. Define the scope: One specific spelling, all variants, all regions, or one country?
2. Build a master list: Use GEDminer to extract every individual with the surname (and variants) — export as CSV from the People tab
3. Add unrelated bearers: A one-name study covers everyone with the surname, not just your relatives. Import additional records from civil registration, censuses, and parish registers
4. Map distribution by decade: Track how the surname's geographic footprint changed over time
5. Document patterns: Y-DNA testing across multiple bearers can reveal whether the surname has one origin or several

GEDminer's analysis tools handle steps 2-4 directly; step 5 requires coordinating with DNA testing platforms.

Exporting surname data

For deeper analysis in spreadsheets or specialist software:

• People tab: Filter by surname, then export the filtered list (CSV or XLSX)
• Locations tab: Export location data with associated individuals
• Migration Analysis: Export migration events as CSV for mapping in GIS tools

Exports include normalised snake_case headers, making them easy to import into Excel, Google Sheets, R, or Python for statistical analysis.