RQ3: Data-to-code relationships

We synthesize 12 recurring relationship families between training-data conditions and observable generated-code outcomes. Evidence includes controlled interventions, corpus audits, output probes, cross-model comparisons, reviews, and authors’ interpretations. Family definitions preserve these differences and their limitations.

Read the relationship graph

Thirteen training-data headings connect through twelve relationship families to eight generated-code dimensions. The graph summarizes 101 assignments from 67 papers; correctness receives 61 assignments.

The manuscript graph. Width represents literature coverage. All percentages use 101 assignments as the denominator.

Explore the interactive graph · Download the manuscript figure (PDF) · Read the data guide

One assignment is a unique (paper, relationship family, RQ2 source, RQ1 outcome) combination. Repeated passages supporting the same combination count once. A paper can contribute several assignments when the relationships differ. The graph contains 101 assignments from 67 papers, linked to 105 evidence records through 107 normalized evidence links. Width is not an effect-size or causal-strength estimate.

Relationship families

Family Assignments Share Papers
F01: Defect-Pattern Carryover 14 13.86% 14
F02: Vulnerability-Pattern Carryover 10 9.90% 10
F03: Restricted/Sensitive-Content Reproduction Risks 8 7.92% 6
F04: Structural-Quality Associations 1 0.99% 1
F05: Clarity-Pattern Associations 2 1.98% 2
F06: Efficiency-Pattern Carryover 4 3.96% 4
F07: Supervision-Signal Quality Associations 12 11.88% 11
F08: Redundancy-Associated Reinforcement and Degeneration 3 2.97% 3
F09: Prevalence-Associated Quality Skew 18 17.82% 17
F10: Underexposure-Associated Quality Gaps 24 23.76% 22
F11: Contamination-Associated Familiarity Differences 3 2.97% 3
F12: Robustness-Pattern Associations 2 1.98% 2

Select a paper count to open that family’s supporting papers. See the operational definitions for routing rules and boundaries, and the assignment table for individual paths. Rounded shares can sum to 99.99%.

What the distribution supports

Correctness accounts for 61/101 assignments (60.4%). Underexposure, prevalence skew, defect carryover, and supervision-signal quality together account for 68/101 (67.3%). These concentrations describe the literature’s attention. Robustness, Maintainability, and Understandability together receive six assignments.

The evidence supports examining example quality, input–target alignment, and coverage against deployment requirements. Interpretation remains study-specific: bundled cleaning may not isolate an individual filter’s effect, hidden corpora limit attribution, and observed associations can have several explanations. The evidence table and path links retain source locations and qualifiers.

Supporting papers

Browse 67 distinct papers by relationship family. Each group contains distinct papers, even when a paper contributes several paths within that family. A paper can appear in several families; group counts are not additive. Stable study IDs trace back to the assignment table and its evidence links.

F01Defect-Pattern Carryover 14 papers
LLMs Meet Library Evolution
LLMs Meet Library Evolution: Evaluating Deprecated API Usage in LLM-based Code Completion
S001 · Jun-24View Paper ↗
CodeHalu
CodeHalu: Investigating Code Hallucinations in LLMs via Execution-based Verification
S010 · May-24View Paper ↗
SStuBs
Large Language Models and Simple, Stupid Bugs
S013 · Mar-23View Paper ↗
package hallucinations
We Have a Package for You! A Comprehensive Analysis of Package Hallucinations by Code Generating LLMs
S014 · Jun-24View Paper ↗
Bugs in LLM-generated Code
Bugs in Large Language Models Generated Code: An Empirical Stud
S021 · Mar-24View Paper ↗
Infinite-Instruct
Infinite-Instruct: Synthesizing Scaling Code instruction Data with Bidirectional Synthesis and Static Verification
S047 · May-25View Paper ↗
Quality In, Quality Out
Quality In, Quality Out: Investigating Training Data's Role in AI Code Generation
S048 · Mar-25View Paper ↗
SwallowCode
Rewriting Pre-Training Data Boosts LLM Performance in Math and Code
S050 · May-25View Paper ↗
Code Pretraining
How Does Code Pretraining Affect Language Model Task Performance?
S063 · Sep-24View Paper ↗
Synthetic Data Generation
Synthetic Data Generation Using Large Language Models: Advances in Text and Code
S086 · Jan-25View Paper ↗
Cracks in The Stack
Cracks in The Stack: Hidden Vulnerabilities and Licensing Risks in LLM Pre-Training Datasets
S087 · May-25View Paper ↗
RTL-Breaker
RTL-Breaker: Assessing the Security of LLMs Against Backdoor Attacks on HDL Code Generation
S089 · Mar-25View Paper ↗
aiXcoder-7B
aiXcoder-7B: A Lightweight and Effective Large Language Model for Code Processing
S094 · Apr-25View Paper ↗
UCD-Training
Unseen-Codebases-Domain Data Synthesis and Training Based on Code Graphs
S100 · Feb-26View Paper ↗
F02Vulnerability-Pattern Carryover 10 papers
Copilot Security
Is GitHub’s Copilot as Bad as Humans at Introducing Vulnerabilities in Code?
S007 · Apr-22View Paper ↗
Purple Llama CYBERSECEVAL
Purple Llama CYBERSECEVAL: A Secure Coding Benchmark for Language Models
S017 · Dec-23View Paper ↗
Lost at C
Lost at C: A User Study on the Security Implications of Large Language Model Code Assistants
S018 · Aug-22View Paper ↗
AI Assistants Security
Do Users Write More Insecure Code with AI Assistants?
S019 · Nov-22View Paper ↗
DeVAIC
DeVAIC: A Tool for Security Assessment of AI-generated Code
S037 · Apr-24View Paper ↗
Codex
Evaluating Large Language Models Trained on Code
S082 · Jul-21View Paper ↗
Cracks in The Stack
Cracks in The Stack: Hidden Vulnerabilities and Licensing Risks in LLM Pre-Training Datasets
S087 · May-25View Paper ↗
RTL-Breaker
RTL-Breaker: Assessing the Security of LLMs Against Backdoor Attacks on HDL Code Generation
S089 · Mar-25View Paper ↗
Llm Hallucinations in Practical Code Generation
Llm hallucinations in practical code generation: Phenomena, mechanism, and mitigation
S112 · Sep-24View Paper ↗
AATK Benchmark
Asleep at the keyboard? assessing the security of github copilot's code contributions
S114 · Aug-21View Paper ↗
F03Restricted/Sensitive-Content Reproduction Risks 6 papers
DeSec
Decoding Secret Memorization in Code LLMs Through Token-Level Characterization
S030 · Oct-24View Paper ↗
Artificial-Intelligence Generated Code Considered Harmful
Artificial-Intelligence Generated Code Considered Harmful: A Road Map for Secure and High-Quality Code Generation
S041 · Sep-24View Paper ↗
CodeMI
Does Your Neural Code Completion Model Use My Code? A Membership Inference Approach
S075 · Apr-24View Paper ↗
Codex
Evaluating Large Language Models Trained on Code
S082 · Jul-21View Paper ↗
Cracks in The Stack
Cracks in The Stack: Hidden Vulnerabilities and Licensing Risks in LLM Pre-Training Datasets
S087 · May-25View Paper ↗
Code Generation Survey
A Survey on Large Language Models for Code Generation
S091 · Aug-24View Paper ↗
F04Structural-Quality Associations 1 paper
CodeSmellEval
How Propense Are Large Language Models at Producing Code Smells? A Benchmarking Study
S065 · Dec-24View Paper ↗
F05Clarity-Pattern Associations 2 papers
Synthetic Data Generation
Synthetic Data Generation Using Large Language Models: Advances in Text and Code
S086 · Jan-25View Paper ↗
ShortCoder
ShortCoder: Knowledge-Augmented Syntax Optimization for Token-Efficient Code GenerationPreprint
S103 · Jan-26View Paper ↗
F06Efficiency-Pattern Carryover 4 papers
EffiBench
EffiBench: Benchmarking the Efficiency of Automatically Generated Code
S011 · Feb-24View Paper ↗
Mercury
Mercury: A Code Efficiency Benchmark for Code Large Language Models
S012 · Feb-24View Paper ↗
RTL-Breaker
RTL-Breaker: Assessing the Security of LLMs Against Backdoor Attacks on HDL Code Generation
S089 · Mar-25View Paper ↗
ShortCoder
ShortCoder: Knowledge-Augmented Syntax Optimization for Token-Efficient Code GenerationPreprint
S103 · Jan-26View Paper ↗
F07Supervision-Signal Quality Associations 11 papers
Less is More
Less is More: On the Importance of Data Quality for Unit Test Generation
S002 · Feb-25View Paper ↗
Large Language Models for Code
Large Language Models for Code: Security Hardening and Adversarial Testing
S016 · Feb-23View Paper ↗
CIDRe
CIDRe: A Reference-Free Multi-Aspect Criterion for Code Comment Quality Measurement
S046 · May-25View Paper ↗
Data-efficient Fine-tuning
Data-efficient LLM Fine-tuning for Code Generation
S059 · Apr-25View Paper ↗
CRPE
CRPE: Expanding The Reasoning Capability of Large Language Model for Code Generation
S060 · May-25View Paper ↗
DeepSeek-Coder
DeepSeek-Coder: When the Large Language Model Meets Programming -- The Rise of Code Intelligence
S061 · Jan-24View Paper ↗
Brevity is the soul of wit
Brevity is the soul of wit: Pruning long files for code generation
S071 · Jul-24View Paper ↗
Benchmark Builders
Large Language Models are Qualified Benchmark Builders: Rebuilding Pre-Training Datasets for Advancing Code Intelligence Tasks
S072 · Apr-25View Paper ↗
MG-Verilog
MG-Verilog: Multi-grained Dataset Towards Enhanced LLM-assisted Verilog Generation
S090 · Jun-24View Paper ↗
Code Generation Survey
A Survey on Large Language Models for Code Generation
S091 · Aug-24View Paper ↗
DataRecipe
DataRecipe --- How to Cook the Data for CodeLLM?
S092 · Oct-24View Paper ↗
F08Redundancy-Associated Reinforcement and Degeneration 3 papers
CodeHalu
CodeHalu: Investigating Code Hallucinations in LLMs via Execution-based Verification
S010 · May-24View Paper ↗
Data-efficient Fine-tuning
Data-efficient LLM Fine-tuning for Code Generation
S059 · Apr-25View Paper ↗
Code Copycat Conundrum
Code Copycat Conundrum: Demystifying Repetition in LLM-based Code Generation
S108 · Apr-25View Paper ↗
F09Prevalence-Associated Quality Skew 17 papers
LLMs Meet Library Evolution
LLMs Meet Library Evolution: Evaluating Deprecated API Usage in LLM-based Code Completion
S001 · Jun-24View Paper ↗
Phi-4
Phi-4 Technical Report
S006 · Dec-24View Paper ↗
EffiBench
EffiBench: Benchmarking the Efficiency of Automatically Generated Code
S011 · Feb-24View Paper ↗
CloudAPIBench
On Mitigating Code LLM Hallucinations with API Documentation
S024 · Jul-24View Paper ↗
AutoAPIEval
A Comprehensive Framework for Evaluating API-oriented Code Generation in Large Language Models
S029 · Sep-24View Paper ↗
Unveiling Inefficiencies in LLM-Generated Code
Unveiling Inefficiencies in LLM-Generated Code: Toward a Comprehensive Taxonomy
S042 · Mar-25View Paper ↗
Data-efficient Fine-tuning
Data-efficient LLM Fine-tuning for Code Generation
S059 · Apr-25View Paper ↗
Code Pretraining
How Does Code Pretraining Affect Language Model Task Performance?
S063 · Sep-24View Paper ↗
StarCoder 2 and The Stack v2
StarCoder 2 and The Stack v2: The Next Generation
S064 · Feb-24View Paper ↗
Code Data Training Stage
At Which Training Stage Does Code Data Help LLMs Reasoning?
S069 · Sep-23View Paper ↗
Beyond Correctness
Beyond Correctness: Benchmarking Multi-dimensional Code Generation for Large Language Models
S073 · Jul-24View Paper ↗
Codex
Evaluating Large Language Models Trained on Code
S082 · Jul-21View Paper ↗
Path Planning Evaluation
Assessing LLM code generation quality through path planning tasks
S083 · Apr-25View Paper ↗
MG-Verilog
MG-Verilog: Multi-grained Dataset Towards Enhanced LLM-assisted Verilog Generation
S090 · Jun-24View Paper ↗
aiXcoder-7B
aiXcoder-7B: A Lightweight and Effective Large Language Model for Code Processing
S094 · Apr-25View Paper ↗
APIKG4SYN
Framework-Aware Code Generation with API Knowledge Graph-Constructed Data: A Study on HarmonyOS
S104 · Nov-25View Paper ↗
AATK Benchmark
Asleep at the keyboard? assessing the security of github copilot's code contributions
S114 · Aug-21View Paper ↗
F10Underexposure-Associated Quality Gaps 22 papers
Qwen
Qwen Technical Report
S003 · Sep-23View Paper ↗
Qwen2
Qwen2 Technical Report
S004 · Jul-24View Paper ↗
HalluCode
Exploring and Evaluating Hallucinations in LLM-Powered Code Generation
S009 · Apr-24View Paper ↗
CodeHalu
CodeHalu: Investigating Code Hallucinations in LLMs via Execution-based Verification
S010 · May-24View Paper ↗
package hallucinations
We Have a Package for You! A Comprehensive Analysis of Package Hallucinations by Code Generating LLMs
S014 · Jun-24View Paper ↗
HallTrigger
Code Hallucination
S015 · Jul-24View Paper ↗
ChatGPT Code Quality
No Need to Lift a Finger Anymore? Assessing the Quality of Code Generation by ChatGPT
S023 · Aug-23View Paper ↗
When Fine-Tuning LLMs Meets Data Privacy
When Fine-Tuning LLMs Meets Data Privacy: An Empirical Study of Federated Learning in LLM-Based Program Repair
S031 · Dec-24View Paper ↗
DeVAIC
DeVAIC: A Tool for Security Assessment of AI-generated Code
S037 · Apr-24View Paper ↗
Software Librarian
Is ChatGPT a Good Software Librarian? An Exploratory Study on the Use of ChatGPT for Software Library Recommendations
S039 · Aug-24View Paper ↗
Infinite-Instruct
Infinite-Instruct: Synthesizing Scaling Code instruction Data with Bidirectional Synthesis and Static Verification
S047 · May-25View Paper ↗
Security and Quality in LLM-Generated Code
Security and Quality in LLM-Generated Code: A Multi-Language, Multi-Model Analysis
S049 · Feb-25View Paper ↗
ReCode
ReCode: Updating Code API Knowledge with Reinforcement Learning
S057 · Jun-25View Paper ↗
WaveCoder
WaveCoder: Widespread And Versatile Enhancement For Code Large Language Models By Instruction Tuning
S070 · Dec-23View Paper ↗
RedStone
RedStone: Curating General, Code, Math, and QA Data for Large Language Models
S080 · Dec-24View Paper ↗
Code Llama
Code Llama: Open Foundation Models for Code
S081 · Aug-23View Paper ↗
Code Generation Survey
A Survey on Large Language Models for Code Generation
S091 · Aug-24View Paper ↗
UCD-Training
Unseen-Codebases-Domain Data Synthesis and Training Based on Code Graphs
S100 · Feb-26View Paper ↗
APIKG4SYN
Framework-Aware Code Generation with API Knowledge Graph-Constructed Data: A Study on HarmonyOS
S104 · Nov-25View Paper ↗
MultiCodeIF
A hierarchical and evolvable benchmark for fine-grained code instruction following with multi-turn feedback
S105 · Jul-25View Paper ↗
RustEvo^ 2
RustEvo^ 2: An Evolving Benchmark for API Evolution in LLM-based Rust Code Generation
S110 · Mar-25View Paper ↗
Llm Hallucinations in Practical Code Generation
Llm hallucinations in practical code generation: Phenomena, mechanism, and mitigation
S112 · Sep-24View Paper ↗
F11Contamination-Associated Familiarity Differences 3 papers
Beyond Correctness
Beyond Correctness: Benchmarking Multi-dimensional Code Generation for Large Language Models
S073 · Jul-24View Paper ↗
Unseen Horizons
Unseen Horizons: Unveiling the Real Capability of LLM Code Generation Beyond the Familiar
S088 · Apr-25View Paper ↗
LLM-ProS
LLM-ProS: Analyzing Large Language Models’ Performance in Competitive Problem Solving
S097 · May-25View Paper ↗
F12Robustness-Pattern Associations 2 papers
Less is More
Less is More: On the Importance of Data Quality for Unit Test Generation
S002 · Feb-25View Paper ↗
Beyond Functional Correctness
Beyond functional correctness: Investigating coding style inconsistencies in large language models
S106 · Jun-24View Paper ↗

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