The Sales Comparison Approach (SCA) is one of the most popular when it comes to real estate appraisal. Used as a reference in real estate expertise and as one of the major types of Automatic Valuation Models (AVM), it recently gained popularity within machine learning methods. The performance of models able to use data represented as sets and graphs made it possible to adapt this methodology efficiently, yielding substantial results. SCA relies on taking past transactions (comparables) as references, selected according to their similarity with the target property's sale. In this study, we focus on the selection of these comparables for real estate appraisal. We demonstrate that the selection of comparables used in many state-of-the-art algorithms can be significantly improved by learning a selection policy instead of imposing it. Our method relies on a hybrid vector-geographical retrieval module capable of adapting to different datasets and optimized jointly with an estimation module. We further show that the use of carefully selected comparables makes it possible to build models that require fewer comparables and fewer parameters with performance close to state-of-the-art models. All our evaluations are made on five datasets which span areas in the United States, Brazil, and France.
Figures & tables
Figure 1: Model architecture. Red rows represent the target property whose price is estimated; blue rows represent comparables picked via vector retrieval; yellow rows represent comparables picked via geographic retrieval; bi-color rows represent features relative to the target; grey shaded rectangles and dashed lines are the modules added to REA to form EREA.
Region
Attr.
Samples
Value (€/ m2 , ,R)
Dist. (m)
IV
22
45,554
2,613 ± 1,278
353 ± 628
KC
19
21,608
540,098 ± 367,156
604 ± 940
FC
12
83,067
155,288 ± 76,420
98 ± 148
POA
8
15,368
443,798 ± 228,518
202 ± 268
SP
8
68,848
741,952 ± 411,643
202 ± 246
Table 1: Dataset statistics. Values and distances are calculated w.r.t the 40 geographically closest comparables.
Figure 2: The temporal split of the IV dataset into offset, train, validation, test.
Figure 3: Intrinsic retrieval evaluation with REA. Geographic retrieval (yellow), hybrid retrieval (green), and vector retrieval (blue), are compared with different number of comparables. The average and 95% CI of 20 simulations are shown here.
Model
IV
KC
FC
POA
SP
MdAE
MdABRE
MdAE
MdABRE
MdAE
MdABRE
MdAE
MdABRE
MdAE
MdABRE
LR
574
21.21
68568
16.96
20259
16.66
82831
25.57
136263
25.70
kNN
467
19.24
68112
16.83
12255
9.55
40000
11.18
108381
19.73
XGB
408
16.08
39485
9.26
9990
7.72
44548
12.41
69212
11.93
ASI
357.16*
13.24*
36559.8
8.37
8608.5
6.55
34281.1
9.57
58194.7
10.0
± 2.75
± 0.09
± 224.3
± 0.05
± 40.4
± 0.03
± 408.2
± 0.1
± 1496.1
± 0.24
Table 2: Baseline comparison table on all 5 datasets. MdAE is in €/ m2 for IV, forKC/FCandR for POA/SP, MdABRE is in %. The average and 95% CI of 20 simulations are shown here for the last 3 models. ASI was adapted into PyTorch for the IV dataset and might differ slightly, hence the asterisk.
Model
IV
KC
FC
POA
SP
ASI
11,660
21,700
17,140
19,240
3,565
REA
900
800
660
580
580
EREA
1,472
1,142
792
592
592
Table 3: Number of parameters per model and dataset.
Real estate valuation is a structured regression problem in which prices are governed by heterogeneous feature types, sparse regional effects, nonlinear interactions, and the practical logic of comparable properties. Standard multilayer perceptrons treat each row as an isolated vector and must learn locality, scale sensitivity, and categorical matching from supervision alone. Gradient-boosted decision trees provide strong tabular baselines, but their feature-centric splitting mechanism does not explicitly model the retrieval of similar historical observations. This paper presents RowNet, a retrieval-based neural architecture for real estate price-per-square-meter prediction. RowNet represents a query property through pairwise similarity features against a memory bank of labeled properties. A first retrieval layer estimates a coarse target from feature-only similarities. A second layer augments the memory comparison with target-consistency features and uses multiple learned attention heads to retrieve complementary comparable sets. A final mixture-of-experts module combines learned gating, residual correction, entropy regularization, and head-diversity regularization to produce the prediction.
Askat Rakhymbekov, Gulshat Muhametjanova
Department of Applied Mathematics and Informatics Kyrgyz-Turkish Manas University Bishkek, Kyrgyzstan · Department of Applied Mathematics and Informatics2026 Kyrgyz-Turkish Manas University Bishkek, KyrgyzstanJun
Benchmarks of machine learning models often include many datasets, making evaluation expensive. For efficiency, it is preferable to perform evaluations on small, representative datasets instead. The selection of such subsets typically relies on heuristics and is rarely analyzed for the robustness of the resulting model rankings. We introduce a framework to perform the task of selecting datasets subsets with an evaluation of how different selection strategies preserve the global model rankings. Our framework includes bootstrap aggregation, which provides valid confidence intervals, allowing a principled comparison of selection strategies. We consider clustering, design criteria (A/D-optimality), random baselines, and greedy farthest-first (FAFI). For the latter, we derive upper bounds on selection quality in terms of ranking errors as a function of the number of selected datasets. Empirically, in time series classification (TSC, 112 datasets) and in a supplementary natural language processing benchmark derived from MTEB (57 tasks), several selection strategies improve rank preservation compared with random subsets, including simple FAFI. In contrast, in recommender systems (30 datasets), the improvement of strategies over random selection is small and typically statistically insignificant. For TSC, our best-performing strategy achieves a Spearman correlation of 0.95 with the full benchmark model rankings using only five selected datasets. Additional experiments indicate that the effectiveness of selection approaches depends on both the quality of dataset representations and the scale of the benchmarking regime.
Rostislav Gusev, Alexey Zaytsev
Applied AI Institute Moscow, Moscow region, Russian Federation
Developing agents capable of navigating fragmented, multi-source information remains challenging, primarily due to the scarcity of benchmarks reflecting hybrid workflows combining database querying with external APIs. To bridge this gap, we introduce ReCoQA, a large-scale benchmark of 29,270 real-estate instances featuring machine-verifiable supervision for intermediate steps, including structured intent labels, SQL queries, and API calls. Complementarily, we propose HIRE-Agent, a hierarchical framework instantiating an understand-plan-execute architecture as a strong baseline. By orchestrating a Front-end parser, a planning Supervisor, and execution Specialists, HIRE-Agent effectively integrates heterogeneous evidence. Extensive experiments demonstrate that HIRE-Agent constitutes a strong baseline and substantiates the necessity of hierarchical collaboration for complex, real-world reasoning tasks.
Yindong Zhang, Wenmian Yang, Yiquan Zhang +1
Hong Kong Baptist University · Beijing Normal-Hong Kong Baptist University · Beijing Normal University