Flake Reduction Stage Classifier

Apply explicit caller cortex-band reduction-stage codes without a universal lithic technology rule; cortex alone does not establish the true manufacturing stage.

Description

Cortex coverage can be used in a stated lithic reduction-stage coding policy.

Cortex coverage can be used in a stated lithic reduction-stage coding policy. The coverage measurement and the policy label remain separate from an inferred manufacturing history.^[1]

Apply explicit caller cortex-band reduction-stage codes without a universal lithic technology rule; cortex alone does not establish the true manufacturing stage.

When to use Flake Reduction Stage Classifier

Use this tool to apply explicit caller cortex-band reduction-stage codes without a universal lithic technology rule; cortex alone does not establish the true manufacturing stage.

Prepare the artifact, site or survey measurements and any independently established calibration or model choices. Keep paired observations aligned and confirm units and coordinate conventions.

How to use Flake Reduction Stage Classifier and understand its results

Prepare the artifact, site or survey measurements and any independently established calibration or model choices. Keep paired observations aligned and confirm units and coordinate conventions.
Enter flakeCortexFractions, callerStageLowerEdges, callerStageCodes using the field table and calculation rules, then run the tool.
Read callerReductionStageCodes. 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
flakeCortexFractions	Flake cortex fractions	list of number	Required
callerStageLowerEdges	Caller stage lower edges	list of number	Required
callerStageCodes	Caller stage codes	list of number	Required

Enter cortex fractions in [0,1] and 2–128 strictly increasing caller lower edges in [0,1] beginning at zero, paired with nonnegative integer stage codes. Select the lower-inclusive band for each flake and return its supplied code. An empty flake list returns an empty result.

Paired lists must be nonempty and have equal lengths. Each sequence checked for increasing order must contain at least two strictly increasing values.

stage = caller code at largest lower edge≤cortex fraction

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

Output field	Meaning	Value type
callerReductionStageCodes	Caller reduction stage codes	list of number

json

{
  "input": {
    "flakeCortexFractions": [
      0,
      0.5,
      1
    ],
    "callerStageLowerEdges": [
      0,
      0.3,
      0.7
    ],
    "callerStageCodes": [
      3,
      2,
      1
    ]
  },
  "output": {
    "callerReductionStageCodes": [
      3,
      2,
      1
    ]
  }
}

Limitations and assumptions

No universal stage boundaries are built in. Cortex alone does not establish the true stage of reduction or a specific lithic technology.

Numeric inputs must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Numeric lists are limited to 100,000 entries; the rules above may require smaller limits. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.

Alternative or Complementary methods

Use Cortex Percentage Flake Estimator: Summarize measured dorsal cortex coverage per flake and pooled physical area, distinguishing unequal-sized flakes from a mean percentage. For a complementary task, use Lithic Debitage Size Class Count Tool: Bin measured flake maximum dimension into explicit half-open lower-edge classes with an open-ended last bin; exact boundaries enter the higher class and manufacture stages are not inferred.

References

Flake Reduction Stage Classifier — tool.io

Similar or alternative tools

Cortex Percentage Flake Estimator
Summarize measured dorsal cortex coverage per flake and pooled physical area, distinguishing unequal-sized flakes from a mean percentage.
Lithic Debitage Size Class Count Tool
Bin measured flake maximum dimension into explicit half-open lower-edge classes with an open-ended last bin; exact boundaries enter the higher class and manufacture stages are not inferred.