Although many aspects of fairness are not captured in quantitative fairness metrics, and it is not possible to fully remove bias from a system to guarantee fairness, you are still responsible to detect and to mitigate fairness issues as much as possible.
When you are working with machine learning models, it is important to understand your models by means of assuring their interpretability and by assessing and mitigating unfairness.
1. **Identify harms (and benefits)**. The first step is to identify harms and benefits. Think about how actions and decisions can affect both potential customers and a business itself.
1. **Identify the affected groups**. Once you understand what kind of harms or benefits that can occur, identify the groups that may be affected. Are these groups defined by gender, ethnicity, or social group?
**False negatives** (reject, but Y=1) - in this case, an applicant who will be capable of repaying a loan is rejected. This is an adverse event because the resources of the loans are withheld from qualified applicants.
**False positives** (accept, but Y=0) - in this case, the applicant does get a loan but eventually defaults. As a result, the applicant's case will be sent to a debt collection agency which can affect their future loan applications.
The next step is to determine which groups are likely to be affected. For example, in case of a credit card application, a model might determine that women should receive much lower credit limits compared with their spouses who share household assets. An entire demographic, defined by gender, is thereby affected.
✅ 今後の"クラスタリング"のレッスンでは、この"混同行列"をコードで構築する方法をご紹介します。
### Define fairness metrics
| | 偽陽性率 | 偽陰性率 | サンプル数 |
You have identified harms and an affected group, in this case, delineated by gender. Now, use the quantified factors to disaggregate their metrics. For example, using the data below, you can see that women have the largest false positive rate and men have the smallest, and that the opposite is true for false negatives.
✅ In a future lesson on Clustering, you will see how to build this 'confusion matrix' in code
This table tells us several things. First, we note that there are comparatively few non-binary people in the data. The data is skewed, so you need to be careful how you interpret these numbers.
In this case, we have 3 groups and 2 metrics. When we are thinking about how our system affects the group of customers with their loan applicants, this may be sufficient, but when you want to define larger number of groups, you may want to distill this to smaller sets of summaries. To do that, you can add more metrics, such as the largest difference or smallest ratio of each false negative and false positive.
✅ 一旦ここで考えてみてください:ローン申請の際に影響を受けそうな他のグループは?
✅ Stop and Think: What other groups are likely to be affected for loan application?
To mitigate unfairness, explore the model to generate various mitigated models and compare the tradeoffs it makes between accuracy and fairness to select the most fair model.
This introductory lesson does not dive deeply into the details of algorithmic unfairness mitigation, such as post-processing and reductions approach, but here is a tool that you may want to try.
The tool helps you to assesses how a model's predictions affect different groups, enabling you to compare multiple models by using fairness and performance metrics, and supplying a set of algorithms to mitigate unfairness in binary classification and regression.
- Learn how to use the different components by checking out the Fairlearn's [GitHub](https://github.com/fairlearn/fairlearn/)
- Learn [how to enable fairness assessments](https://docs.microsoft.com/azure/machine-learning/how-to-machine-learning-fairness-aml?WT.mc_id=academic-15963-cxa) of machine learning models in Azure Machine Learning.
- Check out these [sample notebooks](https://github.com/Azure/MachineLearningNotebooks/tree/master/contrib/fairness) for more fairness assessment scenarios in Azure Machine Learning.
In this lesson, you have learned some basics of the concepts of fairness and unfairness in machine learning.
このレッスンでは、機械学習における公平、不公平の概念の基礎を学びました。
Watch this workshop to dive deeper into the topics:
- YouTube: Fairness-related harms in AI systems: Examples, assessment, and mitigation by Hanna Wallach and Miro Dudik [Fairness-related harms in AI systems: Examples, assessment, and mitigation - YouTube](https://www.youtube.com/watch?v=1RptHwfkx_k)
このワークショップを見て、トピックをより深く理解してください:
Also, read:
- YouTube: AIシステムにおける公平性に関連した被害: Hanna Wallach、Miro Dudikによる、事例、評価、緩和策について[AIシステムにおける公平性に関連した被害: Hanna Wallach、Miro Dudikによる、事例、評価、緩和策について - YouTube](https://www.youtube.com/watch?v=1RptHwfkx_k)
- Microsoft’s RAI resource center: [Responsible AI Resources– Microsoft AI](https://www.microsoft.com/ai/responsible-ai-resources?activetab=pivot1%3aprimaryr4)
- MicrosoftのRAIリソースセンター: [責任あるAIリソース– Microsoft AI](https://www.microsoft.com/ai/responsible-ai-resources?activetab=pivot1%3aprimaryr4)
- Microsoft’s FATE research group: [FATE: Fairness, Accountability, Transparency, and Ethics in AI - Microsoft Research](https://www.microsoft.com/research/theme/fate/)
- MicrosoftのFATE研究グループ: [AIにおけるFATE: Fairness(公平性), Accountability(説明責任), Transparency(透明性), and Ethics(倫理)- Microsoft Research](https://www.microsoft.com/research/theme/fate/)
Explore the Fairlearn toolkit
Fairlearnのツールキットを調べてみましょう
[Fairlearn](https://fairlearn.org/)
- [Fairlearn](https://fairlearn.org/)
Read about Azure Machine Learning's tools to ensure fairness