Hick Choice Reaction Time
Evaluate the equally likely choice form RT = a + b × log2(n), using caller-fitted coefficients in milliseconds. Predictions must be nonnegative; this is a model evaluation without participant calibration.
Description
The equal-choice Hick model relates reaction time to log2 of the number of alternatives.
The equal-choice Hick model relates reaction time to log2 of the number of alternatives. Fitted coefficients provide the task-specific timing scale.1
Evaluate the equally likely choice form RT = a + b × log2(n), using caller-fitted coefficients in milliseconds. Predictions must be nonnegative; this is a model evaluation without participant calibration.
When to use Hick Choice Reaction Time
Use this tool to evaluate the equally likely choice form RT = a + b × log2(n), using caller-fitted coefficients in milliseconds. Predictions must be nonnegative; this is a model evaluation without participant calibration.
Prepare the task-specific rates, comparable response-time means, identified spike train, processed ERP or estimated spectra requested. Confirm units, preprocessing, sample pairing and caller-fitted model coefficients.
How to use Hick Choice Reaction Time and understand its results
- Prepare the task-specific rates, comparable response-time means, identified spike train, processed ERP or estimated spectra requested. Confirm units, preprocessing, sample pairing and caller-fitted model coefficients.
- Enter choices, interceptMs, slopeMsPerBit using the field table and calculation rules, then run the tool.
- Read informationBits, reactionTimeMs. 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 |
|---|---|---|---|
| choices | Number of equally likely choices. | integer; minimum: 1 | Required |
| interceptMs | Fitted intercept a. (ms) | number | Required |
| slopeMsPerBit | Fitted slope b. (ms/bit) | number | Required |
Enter integer choices of at least one and finite fitted intercept/slope. Evaluate the model and reject a nonfinite or negative predicted time. Signed coefficients are permitted if the result is nonnegative; one choice gives zero bits.
informationBits=log2(choices); reactionTimeMs=interceptMs+slopeMsPerBit×informationBits Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.
| Output field | Meaning | Value type |
|---|---|---|
| informationBits | Choice information log2(n). (bit) | number; minimum: 0 |
| reactionTimeMs | Predicted reaction time. (ms) | number; minimum: 0 |
{
"input": {
"choices": 8,
"interceptMs": 200,
"slopeMsPerBit": 50
},
"output": {
"informationBits": 3,
"reactionTimeMs": 350
}
}Limitations and assumptions
No coefficient fitting, participant calibration or unequal-choice entropy calculation is performed. The formula uses log2(n), not log2(n+1).
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 Fitts Law Movement Time: Evaluate the Shannon formulation MT = a + b × log2(1 + D/W), using distance and width in the same units and caller-fitted coefficients in milliseconds. Predictions must be nonnegative. For a complementary task, use Stroop Interference: Calculate the signed stroop interference as mean incongruent response time minus mean congruent response time in milliseconds, using caller-prepared comparable correct-trial means.
References
-
Hick Choice Reaction Time — tool.io
Similar or alternative tools
- Fitts Law Movement Time
Evaluate the Shannon formulation MT = a + b × log2(1 + D/W), using distance and width in the same units and caller-fitted coefficients in milliseconds. Predictions must be nonnegative.
- Stroop Interference
Calculate the signed stroop interference as mean incongruent response time minus mean congruent response time in milliseconds, using caller-prepared comparable correct-trial means.