Doubled Die vs. Double Strike

Classify caller-observed indicators for doubled die vs. double strike while preserving mixed and insufficient evidence.

Description

Doubling and double striking concern different possible stages of production.

Doubling and double striking concern different possible stages of production. This tool organizes declared repeatability, relief and displacement observations into two score groups.^[1]

Classify caller-observed indicators for doubled die vs. double strike while preserving mixed and insufficient evidence.

When to use Doubled Die vs. Double Strike

Use this tool to classify caller-observed indicators for doubled die vs. double strike while preserving mixed and insufficient evidence.

Prepare documented records or observations for the specific coin or issue context. Enter the required labels, reference table or evidence flags and retain the supporting catalog and examination notes for interpretation.

How to use Doubled Die vs. Double Strike and understand its results

Prepare documented records or observations for the specific coin or issue context. Enter the required labels, reference table or evidence flags and retain the supporting catalog and examination notes for interpretation.
Enter repeatsAcrossCoins, raisedRoundedDoubling, wholeDesignDisplaced, secondStrikeOverlap using the field table and calculation rules, then run the tool.
Read classification, firstScore, secondScore. The explanation below defines the units, signs, ordering and any flags or placeholder values.
If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.

Input field	Meaning	Value type; see rules below	Requirement
repeatsAcrossCoins	Repeats across coins	boolean	Required
raisedRoundedDoubling	Raised rounded doubling	boolean	Required
wholeDesignDisplaced	Whole design displaced	boolean	Required
secondStrikeOverlap	Second-strike overlap	boolean	Required

Set the four flags. Count repeatsAcrossCoins, raisedRoundedDoubling for doubled-die and wholeDesignDisplaced, secondStrikeOverlap for double-struck. Both zero yields insufficient-evidence; equal positive scores yield mixed-evidence. Otherwise return the higher-score label with both counts.

firstScore=selected first-side flags; secondScore=selected second-side flags; classification follows their comparison

Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.

Output field	Meaning	Value type
classification	Classification	string; one of "doubled-die", "double-struck", "mixed-evidence", "insufficient-evidence"
firstScore	Doubled-die indicators	integer; minimum: 0
secondScore	Double-strike indicators	integer; minimum: 0

json

{
  "input": {
    "repeatsAcrossCoins": true,
    "raisedRoundedDoubling": true,
    "wholeDesignDisplaced": false,
    "secondStrikeOverlap": false
  },
  "output": {
    "classification": "doubled-die",
    "firstScore": 2,
    "secondScore": 0
  }
}

Limitations and assumptions

No actual die linkage or strike sequence is examined. Unequal mixed evidence is assigned to the higher score rather than returned as mixed.

Numeric inputs must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.

Alternative or Complementary methods

Use Machine vs. Die Doubling: Classify caller-observed indicators for machine vs. die doubling while preserving mixed and insufficient evidence. For a complementary task, use Die Break Stage Classifier: Classify supplied die-break observations without authenticating the coin.

References

Doubled Die vs. Double Strike — tool.io

Similar or alternative tools

Machine vs. Die Doubling
Classify caller-observed indicators for machine vs. die doubling while preserving mixed and insufficient evidence.
Die Break Stage Classifier
Classify supplied die-break observations without authenticating the coin.