CSOCMP5328 - Advanced Machine Learning 

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CSOCMP5328 - Advanced Machine Learning 
Bias and Fairness in Large Language Models (LLMs) 

This is a group assignment, 2 to 3 students only. This is NOT an individual assignment. It is worth 
25% of your total mark. 

  1. Introduction 
    Generative AI models have garnered significant attention and adoption in various domains due to 
    their remarkable output quality. Nevertheless, these models, reliant on massive, internet-sourced 
    datasets, exhibit vulnerabilities that sparked a debate on important ethical concerns, especially 
    around fairness, pertaining to the amplification of human biases and a potential decline in 
    trustworthiness. 

    This assignment aims to investigate methods for bias mitigation within generative AI models and 
    provide your own method to mitigate the bias in the LLMs. While there are two main critical areas: 
    Text-to-Text and Text-to-Image where fairness is paramount, our focus in this assignment is 
    specifically on the Text-to-Text problem. 
    ● Text-to-Text using Large Language Models (LLMs): This area encompasses prominent 
    language models such as Llama-2, BERT, T5, GPT-2/3, and Chat-GPT, and examines the 
    potential for these models to generate biased textual content and its implications. 
    1.1 Common biased categories 
    To contextualise our investigation, we have identified several common categories of bias that 
    may manifest within generative AI models: 
    ● Gender and Occupations: One significant aspect involves exploring biases related to 
    gender disparities in various professions. By analysing the output of generative models, we 
    can discern whether these models tend to associate specific careers more with one gender 
    over another, thus potentially perpetuating occupational stereotypes, for example: 
    ○ Text-to-Text: GPT-2 may generate text that reinforces traditional gender 
    stereotypes. For example, it might associate caregiving with women and leadership 
    with men, perpetuating societal biases. Example: "She is a nurturing mother, 
    always putting her family first." 
    ○ Text-to-Image: The results generated by Stable Diffusion for the prompt “A photo 
    of a firefighter.”  

    ● Race / Ethnicity: Another critical dimension involves assessing biases related to race and 
    ethnicity: 
    ○ Text-to-Text: GPT-2 may generate text that perpetuates racial stereotypes or 
    generalisations about specific racial or ethnic groups, for example: "Asian people 
    are naturally good at math." or the model may generate content that oversimplifies 
    or misrepresents the cultures and traditions of certain racial or ethnic groups. for 
    example: "All Latinos are passionate dancers." 
    ○ Text-to-Image: The bias results for “intelligent person” using Image Search 
    Engines. 


    Addressing bias and fairness in generative AI represents a complex and ongoing challenge. 
    Researchers and developers are actively engaged in devising a range of techniques aimed at bias 
    detection and mitigation. These approaches include the diversification of training data sources, the 
    development of ethical guidelines for AI development, and the creation of algorithms designed 
    explicitly to identify and rectify bias within AI-generated outputs. 
    1.2 Safety 
    Generative AI is used in intentionally harmful ways. This includes misusing generative AI to 
    generate child sexual exploitation and abuse material based on images of children, or generating 
    sexual content that appears to show a real adult and then blackmailing them by threatening to 
    distribute it over the internet. Generative AI can also be used to manipulate and abuse people by 
    impersonating human 代 写CSOCMP5328 - Advanced Machine Learning  conversation convincingly and responding in a highly personalised manner, 
    often resembling genuine human responses. 
    Note: The resultant figures from Stable Diffusion are only presented to demonstrate the bias. This 
    assignment is only for "text-based bias and fairness" in LLMs. 
  2. A Guide to Using the Datasets 
    To effectively investigate and assess bias within generative AI models for Text-to-Text, it is crucial 
    to select appropriate datasets that reflect real-world scenarios and challenges. Depending on your 
    chosen focus, you may need to find specific datasets for your area of investigation e.g., healthcare, 
    sports, entertainment datasets etc. We provide some examples below however you are free to choose any dataset not listed. There are several datasets used for LLM bias evaluation [1], you 
    may refer to this link for more information: github.com/i-gallegos/…
    Those datasets are only used for evaluation, do not train your model with these datasets. 

    Depending on your research objectives, select training datasets that align with your area of 
    investigation. 
    ● Access the chosen datasets through official sources, research papers, or relevant 
    repositories. 
    ● Download the training dataset (s) to your local environment. Ensure that you adhere to any 
    licensing or usage terms associated with the dataset(s). Depending on the debiasing 
    techniques employed, retraining the model may be necessary. Commonly utilised datasets 
    for training LLMs such as Common Crawl, Wikipedia, BookCorpus, PubMed, arXiv, 
    ImageNet, COCO, VQA, Flickr30k, etc. 
    ● Pre-process the dataset as necessary for compatibility with your chosen de-biasing (i.e., 
    enabling fairness) methods in generative AI model. Consider factors like label imbalance 
    among various demographic groups in the training data, as this can lead to bias. One 
    common method for addressing bias is counterfactual data augmentation (CDA) [1] to 
    balance labels. Additionally, other pre-processing techniques involve adjusting harmful 
    information in the data or eliminating potentially biased texts. Identify and handle harmful 
    text subsets using different methods to ensure a fairer training corpus. 
    ● Integrate the pre-processed dataset(s) into your code for training and evaluation. Ensure 
    that you have the appropriate data loading and pre-processing routines in place to work 
    seamlessly with generative AI models. 

    Remember that data pre-processing and formatting are crucial steps in ensuring that the datasets 
    are ready for input into your generative AI models. Additionally, make sure to document your 
    dataset selection and pre-processing steps thoroughly in your research report for transparency and 
    reproducibility. 
  3. Performance Evaluations 
    Most fairness metrics for LLMs can be categorised by what they use from the model such as the 
    embeddings, probabilities, or generated text, including: 
    ● Embedding-based metrics: Using the dense vector representations to measure bias, which 
    are typically contextual sentence embeddings. 
    ● Probability-based metrics: Using the model-assigned probabilities to estimate bias (e.g., to 
    score text pairs or answer multiple-choice questions). 
    ● Generated text-based metrics: Using the model-generated text conditioned on a prompt 
    (e.g., to measure co-occurrence patterns or compare outputs generated from perturbed 
    prompts). 


    4. Tasks 
    Your main tasks are: 

    ● Research: Conduct in-depth research to identify various methods for addressing bias in 
    Generative AI. Ensure you understand the theoretical foundations and practical 
    implementation of these methods. Provide comprehensive comparison of various methods 
    based on the conducted evaluations and discuss their contributions, evaluation methods, 
    strengths, and weaknesses (this will help in the Related Work section of the report). 

    ● Proposed Mathematical Model: 
    ○ Chose a language model such as Llama-2, BERT, T5, GPT-2/3, and Chat-GPT you 
    would like to remove the bias. Write mathematical model for your proposed 
    approach, represent training datasets as a database or feature sets etc., preprocessing
    steps that you have taken on the training datasets, the objective and 
    optimisation method that you employed, training model using LLM, and evaluation 
    metrics to evaluate your model. Write comprehensive table to show all the notations 
    along with their descriptions. 
    ○ Write algorithms to show all the steps of the proposed approach, including system 
    initialisation, training/testing, bias evaluations, results evolutions, or any other 
    steps that show the implementation of your proposed approach. 
    ○ Show schematic representation of your proposed approach. 
    ● Code Development: 
    ○ Implement the selected bias mitigation methods, based on the proposed 
    mathematical model. 
    ○ Train the model using selected LLM with the pre-processed dataset (if needed). 
    ○ Evaluate the bias, show experimental evaluations of various metrics, generate their 
    corresponding figures. 
    ○ The code (including interfacing for training model using LLM and results 
    evaluations) must be written in Python 3. You are allowed to use any external 
    libraries for performance comparisons; however, you need to provide details on 
    how the libraries were setup and how evaluation metrics were used, in the Appendix 
    section. 

    ● Evaluation: 
    ○ Perform the chosen model before applying debiasing techniques on evaluation 
    datasets and show if the bias exists via various prompts, these results are termed as 
    the baseline. 
    ○ Pre-process the dataset and train the model using LLM using your proposed 
    method. Evaluate the performance of the trained model via various prompts to 
    demonstrate that you have addressed the bias. Note that, some debiasing techniques 
    may not require retraining the model. 
    ○ Compare the performance of proposed method with the baseline. 
    ○ Evaluate other performance evaluation metrics, e.g., utility, training time, average, 
    St. Dev etc. Note that some of the evaluation metrics might not be applicable in 
    your proposed scenario, hence, you must actively think of various evaluation 
    metrics to determine the applicability of your model; comprehensive literature survey will help you find how authors evaluated the bias and enabled fairness of 
    generative AI models. 
    ○ Important: Please note that this is our understanding of how to carry out this study 
    and evaluations i.e., show bias of chosen model via prompts à apply chosen 
    debiasing technique (for example, pre-process the dataset (to remove imbalance 
    labels and re-train model with pre-processed dataset) à via prompts, show that you 
    have addressed the bias à compare baseline with proposed approach. If you think 
    that this might not work, you need to come up with other techniques. 

    ● Conclude: 
    ○ Conclude your findings and show the strengths and weaknesses of your proposed 
    approach. 
    ○ Provide hypothetical comparison of your approach with other approaches in the 
    literature. This comparison could be based on various performance metrics. 
    ○ Provide future research directions about how to mitigate those weaknesses. 
    ○ Provide comprehensive directions on how your proposed model could be 
    generalised and applicable for various application scenarios e.g., social media 
    applications, stock markets, health or sports analytics etc. 

    Note: Above steps are written with quite details. If you still have any ambiguity about those steps 
    or implementation/technical questions or understanding of the problem scenario, then please do 
    your own research, share your findings on the Ed so that other students could also get idea of how 
    to deal with specific problem steps. Furthermore, please also post your concerns/questions no Ed 
    under the “Assignment 2” thread, our teaching team will be happy to share their experience and 
    suggestions. Please note that this is an open research assignment, use your own creativity and come 
    up with the understanding of this problem scenario and solution. 

    4.1 Report 
    The report should be organised similar to research papers, and should contain at least the following 
    sections: 

    Abstract: 
    • Clearly introduces the topic scenario and its significance. 
    • Provides a concise summary of the proposed evaluation method. 
    • Provide the results from various evaluation metrics. 
    • Conclude your contributions and discuss its applicability in the real-world scenario. 

    Introduction: 
    • Clearly introduces the problem of bias in generative AI and its importance. 
    • Provides a clear and detailed overview of the proposed methods. 
    • Write contributions in detail e.g., pre-processing, experimental setup, mathematical 
    model, proposed evaluation method and metrics, various steps to achieve evaluate your 
    results. 
    • Provide discussion on the key results and show the organisation of your report at the end 
    of this section. 
    Related Work: 
    • Provides a comprehensive review of related debiasing and fairness methods. 
    • Discusses the advantages and disadvantages of the reviewed methods in the literature. 
    • Demonstrates understanding of the existing literature. 
    • Provide a summarised table of the existing works and show their contributions, evaluation 
    method, strengths, and weaknesses of existing work. 

    Proposed Method: 
    • Explains the theoretical foundations of the proposed solution effectively. 
    • Describes the details of debiasing methods clearly, including the objective function. 
    • Presents the algorithmic representation of the proposed solution comprehensively. 
    • Show schematic representation of your proposed approach. 

    Experiments/Evaluations: 
    • Provides a clear description of the experimental setup, including datasets, algorithm 
    evaluations, and metrics. 
    • Presents experimental results effectively, with appropriate figures. 
    • Conducts a thorough analysis and comparison of baseline and proposed method. 
    • Provides detailed insights on the results. 

    Conclusion: 
    • Effectively summarises the methods and results. 
    • Provides valuable insights or suggestions for future work. 
    • Provide strengths and weaknesses of your work, furthermore, provide future directions. 

    References: 
    • Lists all references, cited in the report. 
    • Formats all references consistently and correctly. 

    Appendix: 
    • Provide instructions on how to run your code. 
    • Provide additional/supporting figures or experimental evaluations. 

    Note: Please follow the provided latex format for the report on Canvas. 
  4. Submission guidelines 
  5. Go to Canvas and upload the following files/folders compressed together as a zip file. 
    ● Report (a PDF file) 
    The report should include all member’s details (student IDs and names). 
    ● Code (a folder): 
    ○ Algorithm (a sub-folder): Your code (could be multiple files or a project) ○ Input data (a sub-folder) Empty. Please do NOT include the dataset in the zip file 
    as they are large. Please provide detailed instructions on how the datasets are used 
    and how to download them. We will copy the dataset to the input folder when we 
    test the code. 
  6. A plagiarism checker will be used, both for code and report. 
  7. A penalty of MINUS 20 percent marks (−20%) per day after the due date. The maximum 
    delay is 5 (five) days, after that assignments will not be accepted. 

    Note: Only one student needs to submit the zip file which must be renamed as student ID numbers 
    of all group members separated by underscores, which should contain all the relevant files and 
    report. E.g., “xxxxxxxx_xxxxxxxx_xxxxxxxx.zip”. Please write names and email addresses of 
    each member in the report. 


    Example References: 
  8. Bias and Fairness in Large Language Models: A Survey. Isabel O. Gallegos, Ryan A. 
    Rossi, Joe Barrow, Md Mehrab Tanjim, Sungchul Kim, Franck Dernoncourt, Tong Yu, 
    Ruiyi Zhang, Nesreen K. Ahmed. arxiv.org/abs/2309.00… 
  9. A Survey on Fairness in Large Language Models. Yingji Li, Mengnan Du, Rui Song, Xin 
    Wang, Ying Wang. arxiv.org/abs/2308.10… 
  10. Fair Diffusion: Instructing Text-to-Image Generation Models on Fairness. Felix Friedrich, 
    Manuel Brack, Lukas Struppek, Dominik Hintersdorf, Patrick Schramowski, Sasha 
    Luccioni, Kristian Kersting. arxiv.org/abs/2302.10… 
  11. Stable Bias: Analyzing Societal Representations in Diffusion Models. Alexandra Sasha 
    Luccioni, Christopher Akiki, Margaret Mitchell, Yacine Jernite. 
    arxiv.org/abs/2303.11… 

    6. Marking Rubrics 
    Criterion Marks Comments 

    Coding (30 Marks): 
    • Coding will be run to see whether it works properly and 
    produces the figures and all evaluations demonstrated in 
    the report. 

    Abstract (5 Marks): 
    • Clearly introduces the topic scenario and its 
    significance. (1 Marks) 
    • Provides a concise summary of the proposed evaluation 
    method. (2 Marks) 
    • Provide the results from various evaluation metrics. (1 
    Marks) 
    • Conclude your contributions and discuss its 
    applicability in the real-world scenario. (1 Marks) 

    Introduction (10 Marks): 
    • Clearly introduces the problem of bias in generative AI 
    and its importance. (3 Marks) 
    • Provides a clear and detailed overview of the proposed 
    methods. (3 Marks) 
    • Write contributions in detail e.g., pre-processing, 
    experimental setup, mathematical model, proposed 
    evaluation method and metrics, various steps to achieve 
    evaluate your results. (2 Marks) 
    • Provide discussion on the key results and show the 
    organisation of your report at the end of this section. (2 
    Marks) 

    Related Work (10 Marks): 
    • Provides a comprehensive review of related debiasing 
    and fairness methods. (3 Marks) 
    • Discusses the advantages and disadvantages of the 
    reviewed methods in the literature. (3 Marks) 
    • Demonstrates understanding of the existing literature. (2 
    Marks) 
    • Provide a summarised table of the existing works and 
    show their contributions, evaluation method, strengths, 
    and weaknesses of existing work. (2 Marks) 




    Proposed Method (20 Marks): 
    • Explains the theoretical foundations of the proposed 
    solution effectively. (7 Marks) 
    • Describes the details of debiasing methods clearly, 
    including the objective function. (4 Marks) 
    • Presents the algorithmic representation of the proposed 
    solution comprehensively. (7 Marks) 
    • Shows schematic representation of proposed approach. 
    (2 Marks) 

    Experiments/Evaluations (20 Marks): 
    • Provides a clear description of the experimental setup, 
    including datasets, algorithm evaluations, and metrics. 
    (7 Marks) 
    • Presents experimental results effectively, with 
    appropriate figures. (7 Marks) 
    • Conducts a thorough analysis and comparison of 
    baseline and proposed method. (4 Marks) 
    • Provides detailed insights on the results. (4 Marks) 

    Conclusion (5 Marks): 
    • Effectively summarises the methods and results. (1 
    Marks) 
    • Provides valuable insights or suggestions for future 
    work. (2 Marks) 
    • Provide strengths and weaknesses of your work, 
    furthermore, provide future directions. (2 Marks) References: • Lists all references, cited in the report. • Formats all references consistently and correctly.  Overall Presentation (10 Marks): • Maintains a clear and logical structure throughout the report. (5 Marks) • Demonstrates excellent writing quality, including clarity and coherence. (3 Marks) • Adheres to formatting and citation guidelines consistently. (2 Marks) Total: 100 Marks 
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