---
title: ECE
datasets:
-  
tags:
- evaluate
- metric
description: binned estimator of expected calibration error
sdk: gradio
sdk_version: 3.0.2
app_file: app.py
pinned: false
---

# Metric Card for ECE

***Module Card Instructions:*** *Fill out the following subsections. Feel free to take a look at existing metric cards if you'd like examples.*

## Metric Description
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Expected Calibration Error `ECE` is a standard metric to evaluate top-1 prediction miscalibration. 
It measures the L^p norm difference between a model’s posterior and the true likelihood of being correct.
$$ ECE_p(f)^p= \mathbb{E}_{(X,Y)} \left[\|\mathbb{E}[Y = \hat{y} \mid f(X) = \hat{p}] - f(X)\|^p_p\right]$$, where $\hat{y} = \argmax_{y'}[f(X)]_y'$ is a class prediction with associated posterior probability $\hat{p}= \max_{y'}[f(X)]_y'$.

It is generally implemented as a binned estimator that discretizes predicted probabilities into a range of possible values (bins) for which conditional expectation can be estimated.

As a metric of calibration *error*, it holds that the lower, the better calibrated a model is.
For valid model comparisons, ensure to use the same keyword arguments.


## How to Use
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### Inputs
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### Output Values
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### Examples
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## Limitations and Bias
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See [3],[4] and [5].

## Citation
[1] Naeini, M.P., Cooper, G. and Hauskrecht, M., 2015, February. Obtaining well calibrated probabilities using bayesian binning. In Twenty-Ninth AAAI Conference on Artificial Intelligence.
[2] Guo, C., Pleiss, G., Sun, Y. and Weinberger, K.Q., 2017, July. On calibration of modern neural networks. In International Conference on Machine Learning (pp. 1321-1330). PMLR.
[3] Nixon, J., Dusenberry, M.W., Zhang, L., Jerfel, G. and Tran, D., 2019, June. Measuring Calibration in Deep Learning. In CVPR Workshops (Vol. 2, No. 7).
[4] Kumar, A., Liang, P.S. and Ma, T., 2019. Verified uncertainty calibration. Advances in Neural Information Processing Systems, 32.
[5] Vaicenavicius, J., Widmann, D., Andersson, C., Lindsten, F., Roll, J. and Schön, T., 2019, April. Evaluating model calibration in classification. In The 22nd International Conference on Artificial Intelligence and Statistics (pp. 3459-3467). PMLR.
[6] Allen-Zhu, Z., Li, Y. and Liang, Y., 2019. Learning and generalization in overparameterized neural networks, going beyond two layers. Advances in neural information processing systems, 32.

## Further References
*Add any useful further references.*