xG Shot Quality Lookup

Map actual soccer shot contexts to caller independently calibrated goal probabilities and sum xG; no fabricated distance/angle model, independent-goal joint probability or scoring guarantee.

Description

Expected goals can sum calibrated shot probabilities without requiring independent shots.

Expected goals can sum calibrated shot probabilities without requiring independent shots. The context model must come from the caller.^[1]

The returned values include Caller shot expected goals, Total caller expected goals. The How section below explains the calculation, input rules and interpretation.

When to use xG Shot Quality Lookup

Use xG Shot Quality Lookup when you need to evaluate the supplied records under the calculation and evidence rules below. No fabricated distance/angle model, joint goal probability or scoring guarantee is supplied.

Prepare the observed race, match or training records and the stated units. Supply independently verified rule editions, calibration tables and targets where requested.

How to use xG Shot Quality Lookup and understand its results

Prepare the observed race, match or training records and the stated units. Supply independently verified rule editions, calibration tables and targets where requested.
Enter callerShotContextIds, callerCalibratedShotGoalProbabilities, observedShotContextIds using the field table and calculation rules, then run the tool.
Read callerShotExpectedGoals, totalCallerExpectedGoals. 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
callerShotContextIds	Caller shot context ids	list of string	Required
callerCalibratedShotGoalProbabilities	Caller calibrated shot goal probabilities	list of number	Required
observedShotContextIds	Observed shot context ids	list of string	Required

Enter aligned nonempty unique nonblank context IDs/probabilities 0–1 and a nonempty observed context list. Look up exact IDs without trimming/case folding; missing contexts are input errors. Return shot and total xG.

shotXg=probability at exact context ID; totalXg=sum(shotXg)

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

Output field	Meaning	Value type
callerShotExpectedGoals	Caller shot expected goals	list of number
totalCallerExpectedGoals	Total caller expected goals	number

json

{
  "input": {
    "callerShotContextIds": [
      "a",
      "b"
    ],
    "callerCalibratedShotGoalProbabilities": [
      0.1,
      0.4
    ],
    "observedShotContextIds": [
      "a",
      "b",
      "a"
    ]
  },
  "output": {
    "callerShotExpectedGoals": [
      0.1,
      0.4,
      0.1
    ],
    "totalCallerExpectedGoals": 0.6
  }
}

Limitations and assumptions

No fabricated distance/angle model, joint goal probability or scoring guarantee is supplied.

Numeric inputs, where present, must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Numeric lists are limited to 10,000 entries; string lists to 128 strings of at most 128 characters each. The rules above may impose smaller limits. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.

Alternative or Complementary methods

Use Middle-Third Pass Completion %: Middle-third pass completion pools opportunities across records. Match percentages should not be averaged without exposure weights. For a complementary task, use Match Distance Covered km Calculator: Tracked match distance should preserve missing segment evidence. Unknown segments are excluded rather than extrapolated.

References

xG Shot Quality Lookup — tool.io

Similar or alternative tools

Middle-Third Pass Completion %
Middle-third pass completion pools opportunities across records. Match percentages should not be averaged without exposure weights.
Match Distance Covered km Calculator
Tracked match distance should preserve missing segment evidence. Unknown segments are excluded rather than extrapolated.