Benchmark Types

CCOBRA offers three types of benchmarks, prediction, adaption and coverage, where each allows to evaluate different aspects of the predictive capabilities of a model.

Benchmark Type

Description

prediction

Only pre-training, models may not adjust during prediction phase.

adaption

Pre-training and the possibility to adjust after each prediction.

coverage

The full participant data is given to the model before the prediction phase starts.

Prediction Setting

In the prediction setting, CCOBRA provides training data to the models before the prediction phase begins. The models are then evaluated on the test data, without the possibility to re-adjust their parameterization. The setting can be used to evaluate models developed with population data in mind to models focussing on individual reasoners. While we strongly encourage to create models with individual participants in mind, most existing models are still based on population data. Therefore, it can be important to compare individualized models to the existing population-based models. Using the prediction setting allows this without putting population-based models at an unfair disadvantage due to their incapability to account for individual data.

Adaption Setting

in the adaption setting, CCOBRA provides all available training data to the models (as in the prediction setting). Additionally, models are expected to adjust their parameterization after each prediction. Therefore, CCOBRA calls the adapt function of the model after each call of predict, providing the model with the response that the participant gave to the last task. This allows models to further adapt to the specific individual reasoner at hand over time. However, the interpretation of the performance is more complicated as for the other settings. The performance of a model in this setting does not only depend on it’s ability to represent the respective participant, but also measures how efficiently it uses the given information.

Coverage Setting

The coverage setting is used to evaluate the general ability of a model to account for individual data. When using this setting, CCOBRA provides models with the test data of a participant using the pre_train_person function, before the respective participant has to be predicted. Therefore, models should in theory be able to perfectly predict the responses, as they would just need to replicate the training data. For this reason, models relying on storing the training data (e.g., the MFA model), should not be evaluated using this setting. However, as cognitive models usually only use a small number of meaningful parameters, they might not be able to represent the participant perfectly in their parameter space. The results of this setting should thus be interpreted as a measure for the ability of a model to represent an individual participant.