Alignment Makes Language Models Normative, Not Descriptive
Organizations: Technion – Israel Institute of Technology
Abstract
Post-training alignment optimizes language models to match human preference signals, but this objective is not equivalent to modeling observed human behavior. We compare 120 base-aligned model pairs on more than 10,000 real human decisions in multi-round strategic games - bargaining, persuasion, negotiation, and repeated matrix games. In these settings, base models outperform their aligned counterparts in predicting human choices by nearly 10:1, robustly across model families, prompt formulations, and game configurations. This pattern reverses, however, in settings where human behavior is more likely to follow normative predictions: aligned models dominate on one-shot textbook games across all 12 types tested and on non-strategic lottery choices - and even within the multi-round games themselves, at round one, before interaction history develops. This boundary-condition pattern suggests that alignment induces a normative bias: it improves prediction when human behavior is relatively well captured by normative solutions, but hurts prediction in multi-round strategic settings, where behavior is shaped by descriptive dynamics such as reciprocity, retaliation, and history-dependent adaptation. These results reveal a fundamental trade-off between optimizing models for human use and using them as proxies for human behavior.
Figures & tables
| Cluster | Variant | B | A | |
|---|---|---|---|---|
| Baseline | Standard | 101 | 5 | |
| Framing | Predict human | 105 | 3 | |
| Observer | 92 | 5 | ||
| Reversed roles | 99 | 2 | ||
| Persona | Naive | 104 | 5 | |
| Expert | 101 | 5 |
| Game Type | Base | Al. | Ratio | (binomial) |
|---|---|---|---|---|
| harmony | 12 | 59 | 4.9:1 Al. | |
| concord | 9 | 62 | 6.9:1 Al. | |
| peace | 14 | 57 | 4.1:1 Al. | |
| safecoord | 15 | 56 | 3.7:1 Al. | |
| assurance | 15 | 56 | 3.7:1 Al. | |
| dilemma | 14 | 57 | 4.1:1 Al. |
Appendix figures & tables14 assets
Supplementary material from the paper’s appendix.
Appendix
| # | Base Model | Aligned Model | Size |
|---|---|---|---|
| CodeGemma (1 pair) | |||
| 1 | codegemma-7b | codegemma-7b-it | 7B |
| CodeLlama (6 pairs) | |||
| 2 | CodeLlama-7b-hf | CodeLlama-7b-Instruct-hf | 7B |
| 3 | CodeLlama-7b-Python-hf | CodeLlama-7b-Instruct-hf | 7B |
| 4 | CodeLlama-13b-hf | CodeLlama-13b-Instruct-hf | 13B |
| Cluster | Variant | Modification | OK |
| Baseline | Standard | Reference format | ✓ |
| Framing | Predict human | Sys: “Predict what a participant decided” | ✓ |
| Observer | Sys: external observer | ✓ | |
| Reversed roles | Sys: offeror predicting receiver | ✓ | |
| Persona | Naive | Sys: “No prior experience” | ✓ |
| Expert | Sys: “Behavioral econ researcher” | ✓ |
| Mass / Min-Corr | None | 0.1 | 0.2 | 0.3 | 0.4 | 0.5 |
|---|---|---|---|---|---|---|
| None | 100:20 ( ) | 96:10 ( ) | 88:8 ( ) | 79:6 ( ) | 37:2 ( ) | – |
| 0.5 | 93:16 ( ) | 90:9 ( ) | 83:8 ( ) | 77:6 ( ) | 37:2 ( ) | – |
| 0.6 | 92:13 ( ) | 90:8 ( ) | 83:7 ( ) | 77:5 ( ) | 37:1 ( ) | – |
| 0.7 | 91:9 ( ) | 90:5 ( ) | 83:5 ( ) | 77:4 ( ) | 37:1 ( ) | – |
| 0.8 | 86:6 ( ) | 86:5 ( ) | 81:5 ( ) | 75:4 ( ) | 36:1 ( ) | – |
| 0.9 | 84:4 ( ) | 84:4 ( ) | 79:4 ( ) | 73:4 ( ) | 34:1 ( ) | – |
| Mass / Min-Corr | None | 0.1 | 0.2 | 0.3 | 0.4 | 0.5 |
|---|---|---|---|---|---|---|
| None | 87:33 ( ) | 80:32 ( ) | 52:29 ( ) | 46:7 ( ) | – | – |
| 0.5 | 61:31 ( ) | 58:31 ( ) | 40:28 ( ) | 34:6 ( ) | – | – |
| 0.6 | 58:31 ( ) | 56:31 ( ) | 39:28 ( ) | 33:6 ( ) | – | – |
| 0.7 | 44:22 ( ) | 44:22 ( ) | 38:21 ( ) | 32:4 ( ) | – | – |
| 0.8 | 35:17 ( ) | 35:17 ( ) | 35:17 ( ) | 32:4 ( ) | – | – |
| 0.9 | 31:2 ( ) | 31:2 ( ) | 31:2 ( ) | 28:1 ( ) | – | – |
| Mass / Min-Corr | None | 0.1 | 0.2 | 0.3 | 0.4 | 0.5 |
|---|---|---|---|---|---|---|
| None | 94:26 ( ) | 76:5 ( ) | 61:3 ( ) | 35:1 ( ) | 3:0 ( ) | – |
| 0.5 | 83:16 ( ) | 69:5 ( ) | 55:3 ( ) | 32:1 ( ) | 3:0 ( ) | – |
| 0.6 | 80:16 ( ) | 67:5 ( ) | 53:3 ( ) | 31:1 ( ) | 3:0 ( ) | – |
| 0.7 | 77:14 ( ) | 65:5 ( ) | 52:3 ( ) | 30:1 ( ) | 3:0 ( ) | – |
| 0.8 | 64:7 ( ) | 56:2 ( ) | 46:1 ( ) | 25:1 ( ) | 3:0 ( ) | – |
| 0.9 | 36:1 ( ) | 33:1 ( ) | 27:1 ( ) | 16:1 ( ) | 3:0 ( ) | – |
| Mass / Min-Corr | None | 0.1 | 0.2 | 0.3 | 0.4 | 0.5 |
|---|---|---|---|---|---|---|
| None | 99:21 ( ) | 98:20 ( ) | 95:17 ( ) | 81:13 ( ) | 49:8 ( ) | 4:0 ( ) |
| 0.5 | 99:20 ( ) | 98:19 ( ) | 95:17 ( ) | 81:13 ( ) | 49:8 ( ) | 4:0 ( ) |
| 0.6 | 99:20 ( ) | 98:19 ( ) | 95:17 ( ) | 81:13 ( ) | 49:8 ( ) | 4:0 ( ) |
| 0.7 | 99:20 ( ) | 98:19 ( ) | 95:17 ( ) | 81:13 ( ) | 49:8 ( ) | 4:0 ( ) |
| 0.8 | 99:20 ( ) | 98:19 ( ) | 95:17 ( ) | 81:13 ( ) | 49:8 ( ) | 4:0 ( ) |
| 0.9 | 98:18 ( ) | 97:17 ( ) | 94:15 ( ) | 80:11 ( ) | 48:6 ( ) | 4:0 ( ) |
| Mass / Min-Corr | None | 0.1 | 0.2 | 0.3 | 0.4 | 0.5 |
|---|---|---|---|---|---|---|
| None | 380:100 ( ) | 350:67 ( ) | 296:57 ( ) | 241:27 ( ) | 89:10 ( ) | 4:0 ( ) |
| 0.5 | 336:83 ( ) | 315:64 ( ) | 273:56 ( ) | 224:26 ( ) | 89:10 ( ) | 4:0 ( ) |
| 0.6 | 329:80 ( ) | 311:63 ( ) | 270:55 ( ) | 222:25 ( ) | 89:9 ( ) | 4:0 ( ) |
| 0.7 | 311:65 ( ) | 297:51 ( ) | 268:46 ( ) | 220:22 ( ) | 89:9 ( ) | 4:0 ( ) |
| 0.8 | 284:50 ( ) | 275:43 ( ) | 257:40 ( ) | 213:22 ( ) | 88:9 ( ) | 4:0 ( ) |
| 0.9 | 249:25 ( ) | 245:24 ( ) | 231:22 ( ) | 197:17 ( ) | 85:7 ( ) | 4:0 ( ) |
| Bargaining | Persuasion | Negotiation | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| # | Mass B | Mass A | Corr B | Corr A | Mass B | Mass A | Corr B | Corr A | Mass B | Mass A | Corr B | Corr A |
| 1 | 0.99 | 1.00 | 0.26 | -0.04 | 0.74 | 0.01 | 0.11 | -0.05 | 0.90 | 0.95 | 0.16 | 0.04 |
| 2 | 0.81 | 0.79 | -0.02 | 0.01 | 0.91 | 0.02 | 0.36 | -0.07 | 0.71 | 0.42 | -0.09 | -0.01 |
| 3 | 0.79 | 0.79 | -0.29 | 0.01 | 0.91 | 0.02 | 0.37 | -0.07 | 0.65 | 0.42 | -0.06 | -0.01 |
| 4 | 0.75 | 0.82 | -0.20 | -0.06 | 0.91 | 0.02 | 0.31 | -0.04 | 0.76 | 0.32 | 0.05 | 0.02 |
| 5 | 0.84 | 0.82 | -0.27 | -0.06 | 0.94 | 0.02 | 0.36 | -0.04 | 0.80 | 0.32 | 0.00 | 0.02 |
| Matrix | One-Shot | Lotteries | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| # | Mass B | Mass A | Corr B | Corr A | Mass B | Mass A | Corr B | Corr A | Mass B | Mass A | Corr B | Corr A |
| 1 | 0.99 | 1.00 | 0.41 | 0.32 | 0.81 | 1.00 | -0.02 | -0.05 | 0.93 | 1.00 | 0.10 | 0.45 |
| 2 | 0.99 | 1.00 | 0.35 | -0.05 | 0.88 | 0.99 | -0.00 | 0.05 | 0.98 | 1.00 | 0.29 | 0.55 |
| 3 | 0.99 | 1.00 | 0.39 | -0.05 | 0.88 | 0.99 | -0.01 | 0.05 | 0.97 | 1.00 | 0.22 | 0.55 |
| 4 | 1.00 | 1.00 | 0.43 | 0.18 | 0.82 | 0.98 | -0.02 | -0.00 | 0.96 | 1.00 | 0.29 | 0.67 |
| 5 | 0.99 | 1.00 | 0.36 | 0.18 | 0.82 | 0.98 | 0.06 | -0.00 | 0.96 | 1.00 | 0.31 | 0.67 |
| Family | Parameter | Values | Description |
|---|---|---|---|
| Bargaining | Stakes | 10K, $1M | Total amount to divide |
| Information | Complete, Incomplete | Whether players know each other’s discount factors | |
| Messages | Allowed, Not allowed | Whether free-text messages accompany offers | |
| Discount | 0.8, 0.9, 0.95, 1.0 | Alice’s per-round discount factor | |
| Discount | 0.8, 0.9, 0.95, 1.0 | Bob’s per-round discount factor | |
| Max rounds | 12, | Maximum number of alternating offers |
| Parameter | Value | Filt. | Base | Al. | ||
|---|---|---|---|---|---|---|
| Stakes | $100 | 74 | 46 | 73 | 1 | |
| $10K | 73 | 47 | 69 | 4 | ||
| $1M | 64 | 56 | 62 | 2 | ||
| Information | Complete | 76 | 44 | 72 | 4 | |
| Incomplete | 78 | 42 | 75 | 3 | ||
| Messages | Allowed | 66 | 54 | 64 | 2 |
| Parameter | Value | Filt. | Base | Al. | ||
| Quality prob. | 0.33 | 51 | 69 | 33 | 18 | |
| 0.50 | 4 | 116 | 4 | 0 | ||
| 0.80 | 0 | 120 | – | – | – | |
| Value | 1.2 | 35 | 85 | 31 | 4 | |
| 1.25 | 23 | 97 | 16 | 7 | ||
| 2.0 | 37 | 83 | 33 | 4 |
| Parameter | Value | Filt. | Base | Al. | ||
|---|---|---|---|---|---|---|
| Information | Complete | 21 | 99 | 20 | 1 | |
| Incomplete | 40 | 80 | 39 | 1 | ||
| Messages | Allowed | 28 | 92 | 27 | 1 | |
| Not allowed | 32 | 88 | 31 | 1 | ||
| Max rounds | 10 | 55 | 65 | 54 | 1 | |
| 30 | 7 | 113 | 6 | 1 |
| Game | Round Phase | Filt. | Base | Al. | ||
|---|---|---|---|---|---|---|
| PD | Early (1–3) | 32 | 88 | 12 | 20 | |
| Mid (4–7) | 116 | 4 | 93 | 23 | ||
| Late (8–10) | 119 | 1 | 92 | 27 | ||
| BoS | Early (1–3) | 0 | 120 | – | – | – |
| Mid (4–7) | 11 | 109 | 10 | 1 | ||
| Late (8–10) | 111 | 9 | 93 | 18 |
LLM Alignment
Large language model alignment studies methods for making models follow human intentions, values, and safety constraints across contexts.
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