Vernacular? I Barely Know Her: Challenges with Style Control and Stereotyping
Ankit Aich, Tingting Liu, Salvatore Giorgi, Kelsey Isman, Lyle Ungar, Brenda Curtis
TL;DR
This study evaluates how well state-of-the-art LLMs can be steered to produce text at specific reading levels and in African American English, using prompting and in-context learning across five models. It finds that ICL and prompts meaningfully reduce reading difficulty (mean drop around $9.9$ FK grade points, $p = 0.005$) and increase AAE usage (up to tenfold, $p = 0.007$), but persistent biases and stereotypes in vernacular language remain a major challenge. GPT-4 family models consistently outperform others in readability control, while Llama-3 exhibits high variability and Mistral-Instruct-7B shows competitive performance with fewer parameters. The work highlights both the promise and the risks of style control in educational and cross-cultural contexts, urging stronger instruction tuning, debiasing strategies, and guardrails to ensure safe, inclusive AI-assisted learning.
Abstract
Large Language Models (LLMs) are increasingly being used in educational and learning applications. Research has demonstrated that controlling for style, to fit the needs of the learner, fosters increased understanding, promotes inclusion, and helps with knowledge distillation. To understand the capabilities and limitations of contemporary LLMs in style control, we evaluated five state-of-the-art models: GPT-3.5, GPT-4, GPT-4o, Llama-3, and Mistral-instruct- 7B across two style control tasks. We observed significant inconsistencies in the first task, with model performances averaging between 5th and 8th grade reading levels for tasks intended for first-graders, and standard deviations up to 27.6. For our second task, we observed a statistically significant improvement in performance from 0.02 to 0.26. However, we find that even without stereotypes in reference texts, LLMs often generated culturally insensitive content during their tasks. We provide a thorough analysis and discussion of the results.
