Understanding Explainability in AI: What It Is and How It Works

Conor Bronsdon
Conor BronsdonHead of Developer Awareness
Explainability in AI: Unlocking Transparency | Galileo
13 min readDecember 04 2024

Introduction

You might have noticed that Artificial Intelligence systems are becoming increasingly smarter and more complicated, especially with the rise of deep learning architectures.

Models like GPT-4 run on 1.8 trillion parameters. Therefore, applications built on these architectures are expected to produce complex outputs that could be puzzling without enough context.

Such models are often called “black boxes” because their internal workings are highly intricate and inaccessible. This happens because they have multiple layers and numerous parameters that interact non-linearly.

From a business perspective, understanding the outputs of an AI model helps build trust and reliability for your customers. It also allows you to trace how specific inputs lead to particular outputs, an aspect known as interpretability. Fortunately, explainability addresses this issue.

This comprehensive guide will help you understand explainability in AI, its influence on AI development, and why it matters.

Why Explainability Matters

AI models are supposed to amplify human life, not complicate it. One way it can do that is by becoming a simple tool everyone can use satisfactorily. AI models also have complex use cases, especially in healthcare and finance.

In such fields, the rationale for every output by an AI model needs to be clear because of its impact. Therefore, rather than wondering why the model produced a certain result, you need to be able to identify the reason.

Explainability helps AI developers adopt a responsible approach to AI development. This approach ensures they follow the regulatory measures that make AI safer, secure, and more inclusive.

Understanding Interpretability

The term interpretability comes up when talking about explainability.

Interpretability refers to the degree to which you can comprehend the internal mechanisms of a model. As you can tell, this requires a technical background, unlike explainability, which does not.

An interpretable model lets users see how input features are transformed into outputs. For example, linear regression models are interpretable because one can easily observe how changes in input variables affect predictions.

Interpretability often needs to be clarified with explainability. Interpretability deals with the system's internal workings, while explainability evaluates the justification for a model’s output.

The lack of Interpretability will likely result in a black-box AI model.

How Black-Box Models Work and Their Limitations

If an AI model makes predictions or generates an output, but you can't explain how it arrived at its production, that’s considered a black box AI. Its methodologies, factors, and parameters remain a mystery.

Still, a black box AI model's performance is exceptional, with high accuracy. The only problem with such an AI model is that it lacks transparency. Black box models are untrustworthy because they cannot verify and validate their outputs.

An AI model can be a black box, accidentally or by design. Here’s what that means:

  1. Accidentally - AI models, especially those based on deep learning algorithms, turn out to be black boxes because these algorithms are so complex. In other words, large-scale learning with no supervision makes the AI capable of functioning like a human brain, which is still a mystery to scientists.
  2. By Design - Developers might also decide to obscure the internal workings of an AI model so that the public is not aware of them. This approach protects intellectual property.

Let’s look at the various reasons that result in black boxes.

  • The existence of layered architectures in neural networks

Deep neural networks consist of multiple layers (input, hidden, and output) that transform raw data into outputs. For now, we will not focus on how the ways that these layers work.

If you think about it, the hidden layer makes it hard to decipher what the model’s architecture is doing. As a result, this hinders transparency.

  • The use of non-linear processing

Black-box models use non-linear transformations to capture complex relationships in data. This nonlinearity is a key strength, enabling them to handle diverse data types like images, text, and audio.

Non-linear processing can result in a black box AI model because there’s no direct relationship between the input and the output data.

  • Automatic feature extraction by the model

Unlike traditional models, black-box systems automatically identify and extract relevant features during training. This approach eliminates the need for manual feature engineering.

  • Optimization via backpropagation

In neural networks, backpropagation adjusts weights and biases based on error gradients, optimizing the model's predictions.

As a result, the concept of backpropagation, where the model learns from its errors, can result in a black box if the errors are unknown.

Limitations of Black-Box Models

As you might have guessed, a black box model will eventually have limitations, especially when considering the development of responsible AI.

Lack of Transparency

Black-box models provide outputs without explaining the reasoning behind their decisions. This opacity can make it difficult to trust and adopt these systems in critical applications that require accountability.

Challenges in Debugging Errors

If you encounter an error, it can be challenging to identify which part of the model caused the issue due to the interconnectedness of parameters and layers.

Bias and Fairness Concerns

Sometimes, bias can arise even if the training data has no bias. Therefore, if you cannot tell how the bias developed because the AI model is a black box, it becomes a problem. This is why you need to implement explainability strategies to avoid such issues.

Lack of Compliance with Legal and Ethical Standards

If your model is categorized as a black box, it will not be compliant with regulations such as GDPR, which require systems to provide understandable explanations for automated decisions.

Accuracy at the Expense of Interpretability

Black box models are quite accurate. This is because of their ability to capture complex, non-linear relationships in data. As a result, this leads to a trade-off for interpretability.

Vulnerability to Adversarial Attacks

As you can imagine, black-box models are susceptible to adversarial attacks like prompt injection. This is because small, imperceptible changes to input data can drastically alter predictions. The lack of explainability makes these vulnerabilities harder to detect.

Key Aspects of Explainability

Discussing the main aspects of explainability can help you get a deeper insight into it.

First of all, explainability can be categorized into two main aspects.

Global Explainability

Global explainability refers to understanding a model's overall behavior across all predictions. It aims to provide insights into how different features, including architecture, general rules, and logic, collectively influence the model's output.

It helps identify which features are most important for the model's predictions on average. For example, in a credit scoring model, global explainability can reveal that age and income are significant predictors of creditworthiness across all applicants.

Global explainability helps assess the model's performance and ensures it aligns with business objectives and ethical standards.

Global explainability is more like interpretability since one often investigates the model's internal reasoning when trying to get the big picture.

Local Explainability

Local explainability understands individual predictions made by the model. It seeks to clarify why a specific decision was made for a particular instance rather than providing insights into the model as a whole.

This type of explanation provides detailed reasoning for individual predictions. For instance, if a loan application is denied, local explainability can identify which factors contributed to that decision.

Local explainability helps end-users, such as customers or operators, understand specific decisions that directly impact them.

Techniques for Achieving Explainability in AI

Think of explainability in AI as understanding how a navigator plans a route. When users and stakeholders can see the reasoning behind AI decisions, it becomes easier to identify issues like biases, errors, or misalignments with intended goals. This clarity isn’t just about transparency, building trust, and ensuring the system operates fairly.

Let’s explore some methods to incorporate explainability in AI models.

Model-Agnostic vs. Model-Specific Methods

Broadly, there are two categories of explainability. It can either be model-agnostic or model-specific.

Model-Agnostic Methods

Model-agnostic methods are designed to work with any machine-learning model. That means all models are treated fairly, so all models are considered black boxes.

Here are the standard techniques you’ll be using.

1. SHAP (Shapley Additive Explanations)

SHAP assigns important values to each feature for individual predictions.

SHAP is rooted in game theory. As such, it uses Shapley values to quantify the contribution of each feature to the model's output. It evaluates each prediction the model makes. Then, it provides a clear and consistent explanation of how much each feature influenced that particular outcome.

This method reveals which features have the most significant positive or negative impact on the model's predictions.

2. LIME (Local Interpretable Model-Agnostic Explanations)

LIME has a complementary technique that creates simpler surrogate models that explain complex predictions locally.

To clarify, LIME explains individual predictions by analyzing how a model makes decisions for a specific case rather than focusing on its overall behavior.

This method makes it straightforward to understand why a model made a particular decision, making it easier to identify potential issues or biases in specific cases.

3. Partial Dependence Plots (PDPs)

Partial Dependence Plots (PDPs) visually show how a specific feature impacts the model's predictions on average. They plot predicted outcomes against different values of that feature while keeping other features constant.

This visualization helps illustrate the relationship between the feature and the predictions, making it easier to understand complex, non-linear relationships.

PDPs allow stakeholders to identify trends in how features influence predictions, providing valuable insights for decision-making and model improvements.

Model-Specific Methods

These are designed for specific types of models, leveraging their internal architecture for insights. Examples include:

As the name suggests, these methods are designed for specific types of models. Still, they maintain the same approach as we have seen in model-agnostic methods. They leverage the internal architecture of the model for insights.

Here are standard model-specific methods you will come across.

1. Integrated gradients

Integrated gradients help us understand how each input feature contributes to neural networks' predictions.

To better understand it, imagine you have a model that predicts house prices based on features like size, location, and number of bedrooms. Integrated gradients highlight which features had the most significant impact on the expected cost for a specific house.

Calculating each feature's contribution reveals which factors most influenced the model's decision.

2. Decision tree visualization

This visualization shows how decision trees predict by breaking the data into smaller parts.

A decision tree is like a flowchart where each question leads to a new branch. For example, it might first ask if a house has more than three bedrooms. Depending on the answer, it will follow different paths to reach a final prediction about the house price.

Visualizing this structure helps people understand how the model arrived at its conclusions and makes it easier to explain to others.

3. Attention maps

Attention maps are tools used in natural language processing (NLP) and image recognition models to show which parts of the input data are most important for making predictions.

For instance, in an image recognition task, an attention map might highlight specific areas of an image that influenced the model's decision about what object is present. Similarly, in NLP, attention maps can indicate the most relevant words to understand their meaning.

What You Should Consider When Implementing Explainability Techniques

Complexity vs. Interpretability

  • Highly complex models (e.g., deep neural networks) often require sophisticated techniques for explainability.
  • Simpler models like decision trees may offer intrinsic interpretability.

Audience needs

  • Technical stakeholders: Require detailed and accurate explanations for debugging and optimization.
  • Non-technical stakeholders: These will mostly prefer intuitive, easy-to-understand visualizations and narratives. Consider your customers, for instance.

Scalability and resource constraints

As you know, techniques like SHAP can be computationally intensive for large datasets. Therefore, you need to allocate resources accordingly.

Method Limitations

  • Techniques like LIME may be unstable. As a result, they produce different explanations for slightly altered inputs.
  • On the other hand, post-hoc methods, like SHAP and LIME, may not be as reliable as built-in interpretability.

Benefits of Explainable AI

Explainable AI (XAI) has several key advantages that enhance trust, ensure compliance, optimize performance, and effectively engage stakeholders.

Let’s break down these benefits in simple terms.

User Trust

When you understand how an AI system makes decisions, you’re more likely to trust it.

Imagine you’re using an AI tool in a self-driving car or healthcare. Understanding the reasoning behind its choices is crucial. If you know why the car decided to stop or why a medical recommendation was made, you feel more confident in using that technology.

This transparency is essential for adopting AI, especially in critical areas where safety and well-being are at stake.

Regulatory Compliance and Ethical AI Use

Regulations often require organizations to document how decisions are made, especially when those decisions affect people's lives.

For instance, if an AI system denies a loan application, it should be able to explain why. XAI provides the necessary documentation and helps identify biases in decision-making processes. This way, companies can demonstrate accountability and ensure they are acting fairly.

Enhanced AI Model Performance

Using explainable AI can lead to better AI model performance.

When you understand how a model works, you can identify areas for improvement. For example, if certain features consistently lead to errors, you can refine the model accordingly.

Fostering Stakeholder Confidence

Explainable AI strengthens stakeholder relationships by providing tailored explanations that meet their needs.

Whether you're talking to technical teams, executives, or end-users, XAI can present information in a way that's relevant to each group. This adaptability not only enhances communication but also aligns with broader organizational goals.

When stakeholders understand how AI works and benefits them, they are more likely to support its use.

Challenges in Implementing Explainable AI

Implementing explainable AI comes with several challenges. You must address technical and operational issues to ensure transparency and build trust in the system.

Technical and Operational Challenges in Explainable AI

First, AI models are becoming more complex, which makes it harder to provide consistent and clear explanations. Moreover, as AI systems keep learning, this challenge grows.

On the operational side, aligning the needs of different stakeholders and embedding explainability into existing workflows is often difficult.

Limitations of Current Explainability Models

Current explainability methods like SHAP and LIME offer valuable insights but are limited. They often rely on approximations and need help with unstructured data. As a result, they may also face scalability issues when applied to larger systems.

Potential Risks and Mitigation Strategies

Without explainability, AI systems risk hidden biases and regulatory non-compliance. Robust governance is essential to mitigate these risks. In addition, ongoing research and specialized tools will help maintain transparency and ensure accountability.

Balancing Complexity and Interpretability in AI Systems

Balancing complexity with interpretability is critical. This can be achieved by using hybrid models, adopting advanced techniques, and considering the context of each application. By doing so, you ensure that AI systems are both practical and transparent.

Applications of Local and Global Explanations in Various Sectors

As you will understand, local and global explanations can be used in a sector to understand a model.

This will make sense when you see its applications in these critical sectors.

Automotive Sector

  • Global explanations

Imagine you’re designing a self-driving system like Tesla’s Autopilot.

This system must detect objects, plan routes, and make real-time decisions. Global explanations work like a map of the entire system, showing developers and regulators how it decides what’s most important.

For instance, it reveals whether the car prioritizes lane markings, traffic lights, or nearby vehicles in every situation. By analyzing data from sensors like cameras, LiDAR, and radar, you can spot areas for improvement and fix issues faster.

  • Local explanations

Consider a specific moment, like when the car brakes suddenly or changes lanes. Local explanations zoom in to show why that action happened.

Finance Sector

  • Global explanations

Banking machine learning models analyze transaction size, location, and frequency to spot fraud. Global explanations show how these details work together to improve fraud detection. This helps you refine strategies and meet regulatory demands effectively.

  • Local explanations

When a specific transaction is flagged, local explanations show you why. For example, tools like SHAP might reveal that a high amount paired with a new location raises suspicion. This helps investigators confirm or clear the alert quickly.

Healthcare Sector

  • Global explanations

AI models diagnosing diseases like cancer must show how they make decisions across all cases. Global explanations help you understand the model's reliability and what features it focuses on.

For instance, heat maps from convolutional neural networks (CNNs) highlight key regions in scans, like CT or MRI images, that indicate malignancy. This insight improves training data and fine-tunes the model.

  • Local explanations

When diagnosing a specific case, local explanations zoom in on the exact areas in a scan, like a tumor, that led to the AI's conclusion. This supports doctors in confirming the diagnosis and builds patient trust by aligning AI findings with medical expertise.

E-Commerce Sector

  • Global Explanations

E-commerce platforms rely on global explanations to uncover trends in user behavior. For instance, they might find that product prices and past purchases are the most influential recommendation factors.

  • Local Explanations

When you see a specific recommendation, local explanations clarify the reasoning. For instance, the system might suggest a product because of your browsing history or similar purchases by other users.

  • Global Explanations

Legal AI systems rely on global explanations to show how they analyze factors like case precedents, legal clauses, and jurisdictions. These insights reveal the system’s overall approach to predictions or recommendations, helping you understand its reasoning across cases.

  • Local Explanations

Local explanations highlight the precedents or legal terms that influenced the AI’s decision when focusing on a specific case. This transparency allows lawyers to verify or challenge the system’s suggestions, ensuring its analysis meets legal standards.

The Future of Explainable AI and Ethical Development

As we have seen recently, more AI developers are abandoning black-box AI in favor of explainable AI. Therefore, it’s safe to say this trend will continue as AI grows. Here are more specific trends we expect to see in the future.

Emphasizing Transparency and Accountability

At the heart of XAI is the goal of making AI systems understandable. This transparency builds trust among users, especially in high-stakes areas like healthcare and self-driving cars, where decisions can have serious consequences.

This clarity fosters confidence and aligns with ethical standards that demand accountability in automated decisions.

Responsible Practices in AI Development

Responsible AI development means creating effective, fair, and unbiased systems. Explainable AI helps identify and reduce biases during model training, ensuring equitable decisions.

By clearly documenting how decisions are made, XAI supports compliance with regulations, which is increasingly necessary as governments implement stricter guidelines for AI usage.

Balancing Global and Local Explanations

A key challenge for the future of XAI is balancing global and local explanations. Global explanations show how a model works across all predictions, while local explanations focus on specific instances.

Meeting the diverse needs of stakeholders, from technical experts to everyday users, requires a mix of both types of explanations. This balance enhances overall transparency and trust in AI systems.

The field of XAI is evolving with new techniques that improve understanding and usability. Interactive explanations that adapt to your level of expertise are becoming more common. These tools make complex models accessible by using visuals and simple language.

Additionally, there is a trend toward designing inherently interpretable models, meaning explainability is built into the system from the start.

Strategies for Enterprise Adoption

If you’re looking to adopt XAI solutions, it’s essential to customize approaches to meet stakeholder needs. This involves balancing complexity with interpretability while addressing privacy concerns.

Companies that successfully implement explainable AI will enhance their efficiency and build stronger relationships with customers and regulators.

Ethical Considerations in Deploying XAI Systems

Deploying ethical XAI systems means ensuring fairness, accountability, and transparency while balancing openness with security.

As AI impacts various sectors, upholding ethical norms that respect individual rights and societal values is essential. By prioritizing explainability, organizations can foster trust and comply with emerging regulations.

Embrace Explainable AI for a Transparent Future

Ensure transparency and trust in your AI systems. Galileo's tools provide actionable insights to help you effortlessly explain and optimize AI behavior. We have several advanced tools to help you get started.

FREQUENTLY ASKED QUESTIONS

What is Explainable AI (XAI)?
Explainable AI (XAI) involves methods and tools designed to make AI models transparent, interpretable, and understandable. It allows users and stakeholders to comprehend how AI systems make decisions and generate results.

Why is explainability important in AI systems?
Explainability promotes trust by helping users understand how decisions are made. It also ensures compliance with legal and ethical standards, makes it easier to identify errors and biases, and encourages adoption, especially in high-stakes environments.

How does Explainable AI (XAI) work?
XAI uses techniques like post-hoc analysis (tools such as SHAP and LIME) to clarify predictions, model simplification (using interpretable algorithms like decision trees), and visualization tools to highlight key features or patterns influencing predictions.

Why do we need Explainable AI (XAI)?
XAI is necessary to ensure ethical AI usage, prevent data misuse, improve decision-making, and meet regulatory requirements.

What are global and local explanations?
Global explanations provide an overview of how the model behaves and makes decisions, while local explanations focus on specific predictions and explain why a particular decision was made.

How do these models derive their conclusions?
AI models predict outcomes based on patterns learned from training data. XAI identifies the contribution of various inputs (features) to these decisions using methods like feature importance, saliency maps, or rule-based logic.

How does Explainable AI relate to Responsible AI?
XAI is a key component of Responsible AI, ensuring fairness, accountability, and transparency. It provides visibility into AI operations and helps align models with ethical standards.

Why is performance alone not enough without explainability?
Even high-performing models can make biased or unethical decisions. Explainability ensures models are not only accurate but also trustworthy and ethically aligned.

What are the limitations of Explainable AI (XAI)?
XAI faces challenges like explaining the complexity of deep neural networks, balancing transparency with accuracy, and the resource intensity of explaining large datasets.

Can Explainable AI (XAI) eliminate bias in AI systems?
No, XAI cannot eliminate bias but helps identify and reduce it. Addressing bias requires careful data curation, ethical practices, and continuous monitoring.