Large language models often struggle with complex long-horizon analytical tasks over unstructured tables, which typically feature hierarchical and bidirectional headers and non-canonical layouts. We formalize this challenge as Deep Tabular Research (DTR), requiring multi-step reasoning over interdependent table regions. To address DTR, we propose a novel agentic framework that treats tabular reasoning as a closed-loop decision-making process. We carefully design a coupled query and table comprehension for path decision making and operational execution. Specifically, (i) DTR first constructs a hierarchical meta graph to capture bidirectional semantics, mapping natural language queries into an operation-level search space; (ii) To navigate this space, we introduce an expectation-aware selection policy that prioritizes high-utility execution paths; (iii) Crucially, historical execution outcomes are synthesized into a siamese structured memory, i.e., parameterized updates and abstracted texts, enabling continual refinement. Extensive experiments on challenging unstructured tabular benchmarks verify the effectiveness and highlight the necessity of separating strategic planning from low-level execution for long-horizon tabular reasoning.
Figures & tables
Figure 1: Existing Table QA pipelines (a) are limited to well-structured tables and shallow queries, and fail to handle unstructured tabular properties (b) and long-horizon analytical tasks (c), motivating our Deep Tabular Research.
Figure 2: A sketched overview for our proposed Deep Tabular Research framework for complex unstructured tabular reasoning. DTR decomposes analytical intent into meta operations, plans executable macro paths via expectation-guided search, and executes them with an experience-aware memory that records structured execution feedback and updates planning policies across iterations.
Methods
Accuracy
Analysis Depth
Feasibility
Aesthetics
Avg. Runtime (s) ↓
Total Output Tokens ↓
Avg. LLM Calls ↓
Win Rate
Score Rate
Win Rate
Score Rate
Win Rate
Score Rate
Win Rate
Score Rate
(Tie=0) ↑
(Tie=0.5) ↑
(Tie=0) ↑
(Tie=0.5) ↑
(Tie=0) ↑
(Tie=0.5) ↑
(Tie=0) ↑
(Tie=0.5) ↑
Table specific LLM
TableGPT2-7B
0.20
8.41
5.12
5.12
4.33
4.35
6.21
6.21
3.42
12,450
1.0
TableLLM-7B
0.15
6.22
3.84
3.84
3.10
3.12
4.55
4.55
3.15
10,820
1.0
StructGPT
0.10
4.15
2.10
2.10
1.85
1.86
2.30
2.30
4.88
8,420
1.0
Table 1: Full Comparisons over DTR-Bench to evaluate over accuracy, quality, and efficiency.
Methods
Fact Checking
Numerical Reasoning
Structure Comprehending
Data Analysis
Chart/Report Generation
EM ↑
F1 ↑
EM ↑
F1 ↑
EM ↑
F1 ↑
LLM-EVAL ↑
ROUGE ↑
PASS@1 ↑
ECR ↑
TableGPT2-7B
46.10
53.80
29.31
39.81
48.23
56.68
62.76
33.25
32.47
67.53
TableLLM-7B
38.25
44.12
22.40
31.65
41.10
49.34
55.80
28.42
18.20
42.15
StructGPT
25.40
32.15
14.55
20.80
30.25
38.60
42.33
19.50
5.12
12.44
GPT4o
43.39
51.87
27.63
36.68
42.68
52.89
65.24
33.10
10.39
25.32
DeepSeek-v3
57.21
53.42
47.05
50.61
43.31
74.63
61.40
34.76
9.09
24.68
Table 2: Comparisons over the RealHitBench dataset for five different task types.
Configuration
Meta
QDO
Exp.
Abst.
Acc.
Anal.
Feas.
Aesth.
+ Meta Info
✓
×
×
×
34.8
27.1
25.6
38.2
+ QDO
✓
✓
×
×
36.2
28.8
26.7
40.5
+ Expectation
✓
✓
✓
×
37.1
29.6
27.2
41.8
DTR Full
✓
✓
✓
✓
37.5
30.2
27.6
42.7
Table 3: Architecture ablation study of each components in DTR.
Prompt Strategy
Accuracy
Analysis
Code Error
Avg
Depth
Rate
Calls
No [THINK] (Direct)
35.2
27.8
42.3%
5.8
Simple [THINK] Hint
36.4
28.9
35.6%
5.2
[THINK]+[CODE]
37.5
30.2
28.4%
4.78
Multi-stage Reflection
37.2
29.8
26.1%
5.5
Table 4: Exploration over prompting strategy for think and code.
Figure 3: LLM call budget analysis. The blue curve shows performance (left y-axis) and the purple curve shows marginal gain (right y-axis). DTR’s 4.78-call configuration red star) achieves optimal efficiency by avoiding the plateau region.
Figure 4: Path selection evolution across 10 batches. Colors changing from light blue to deep purple indicate both exploration and exploitation, respectively.
Conduct a risk-return analysis across all {Category} by examining the relationship between {NumericCol1} (returns) and {NumericCol2} (risk metrics). Identify the efficient frontier segments.
Social Researcher
Inequality Analysis
Measure the distribution of {NumericCol} across {Category} using Gini coefficient and decile ratios. Investigate structural factors driving inequality.
Data Analyst
Anomaly Detection
Use statistical methods (z-scores) to identify unusual patterns in {NumericCol} across {Category} . Investigate anomalies and assess impact.
Student/Researcher
Statistical Testing
Conduct rigorous statistical analysis of {NumericCol} across {Category} : test for normality, perform ANOVA/Kruskal-Wallis tests, and calculate effect sizes.
Appendix
Table 6: Representative Question Templates by Persona
Figure 12
Figure 5: Employment Distribution in 1984: Agriculture (4.5%) vs Non-Agriculture (95.5%)
Figure 6: Employment Trends 1983-1990: Employed population grew from 56.8M to 65.1M while unemployed declined from 6.3M to 3.9M
Figure 7: Scatter plot showing the relationship between unemployment rate and civilian labor force size over 16 years (1983-1998)