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.

Description

Lithic size classes summarize measured flake dimensions under explicit boundaries.

Lithic size classes summarize measured flake dimensions under explicit boundaries. Lower-inclusive bins make boundary ties predictable, while the final bin can capture all larger observations.^[1]

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.

When to use Lithic Debitage Size Class Count Tool

Use this tool to 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.

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 Lithic Debitage Size Class Count Tool 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 flakeMaximumDimensionsMm, sizeClassLowerEdgesMm using the field table and calculation rules, then run the tool.
Read sizeClassCounts, sizeClassPercentages. 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
flakeMaximumDimensionsMm	Flake maximum dimensions mm	list of number	Required
sizeClassLowerEdgesMm	Size class lower edges mm	list of number	Required

Enter a nonempty list of nonnegative maximum dimensions in mm and at least two nonnegative strictly increasing class lower edges starting at zero. Use binary search to assign each flake; equality enters the class beginning at that edge. Return class counts and percentages, with the last class open-ended.

Each sequence checked for increasing order must contain at least two strictly increasing values.

bin_i = largest lower-edge index whose edge≤measured dimension

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

Output field	Meaning	Value type
sizeClassCounts	Size class counts	list of number
sizeClassPercentages	Size class percentages	list of number

json

{
  "input": {
    "flakeMaximumDimensionsMm": [
      1,
      5,
      10,
      20
    ],
    "sizeClassLowerEdgesMm": [
      0,
      5,
      10
    ]
  },
  "output": {
    "sizeClassCounts": [
      1,
      1,
      2
    ],
    "sizeClassPercentages": [
      25,
      25,
      50
    ]
  }
}

Limitations and assumptions

The classification uses supplied size boundaries. It does not infer reduction stage, recovery bias or lithic technology, and maximum dimension must use a consistent measurement convention.

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 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. For a complementary task, use Tool to Debitage Ratio: Compare pooled tool/debitage counts corrected with distinct caller recovery probabilities by context; no functional site classification or uncorrected ratio alias.

References

Lithic Debitage Size Class Count Tool — tool.io

Similar or alternative tools

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.
Tool to Debitage Ratio
Compare pooled tool/debitage counts corrected with distinct caller recovery probabilities by context; no functional site classification or uncorrected ratio alias.