Hyper-multi-step: The Truth Behind Difficult Long-context Tasks
Yijiong Yu
2024-10-09

Summary
This paper explores the challenges faced by long-context language models (LCLMs) when dealing with complex tasks and identifies two main reasons for their difficulties: multi-matching retrieval and logic-based retrieval.
What's the problem?
Long-context language models are designed to handle large amounts of text, but they struggle with certain tasks that require them to retrieve multiple pieces of information at once or to use logical reasoning. These tasks are often more complicated than they appear, requiring many steps to solve, which can overwhelm the models.
What's the solution?
The authors conducted experiments to show that the difficulties in these long-context tasks stem from the need for 'hyper-multi-step' reasoning, which involves breaking down problems into many smaller steps. They highlight that simply increasing the amount of information available to the models does not help if they cannot effectively process it. The paper suggests that future research should focus on improving how LCLMs handle these complex, multi-step problems rather than just making them capable of processing more information at once.
Why it matters?
This research is important because it sheds light on why advanced language models struggle with certain tasks and provides a clearer understanding of their limitations. By identifying the specific challenges these models face, researchers can develop better strategies and tools to enhance their performance in real-world applications where complex reasoning is required.
Abstract
Long-context language models (LCLM), characterized by their extensive context window, is becoming increasingly popular. Meanwhile, many long-context benchmarks present challenging tasks that even the most advanced LCLMs struggle to complete. However, the underlying sources of various challenging long-context tasks have seldom been studied. To bridge this gap, we conduct experiments to indicate their difficulty stems primarily from two basic issues: "multi-matching retrieval," which requires the simultaneous retrieval of multiple items, and "logic-based retrieval," which necessitates logical judgment within retrieval criteria. These two problems, while seemingly straightforward, actually exceed the capabilities of LCLMs because they are proven to be hyper-multi-step (demanding numerous steps to solve) in nature. This finding could explain why LLMs struggle with more advanced long-context tasks, providing a more accurate perspective for rethinking solutions for them.