SyncValsverifier → artifact → classifier → verdict
SyncVals · Trajectory

lending-club-lgd-bias-correction-r

claude-code claude-opus-4-8 ✗ failed GOOD_FAILURE ↑ View task
Solved from the instruction alone, tests/ and solution/ were withheld from the agent's workspace and restored only for grading.
Reward = tests/test.sh exit code (0 → resolved); the classification below is post-hoc and cannot change it.
Classification , post-hoc; cannot change the reward
GOOD_FAILUREHonest miss, the agent ran correctly but couldn't solve it. Expected for a hard task; the task is sound.
SubtypeInsufficient Exploration
EvidenceAgent correctly identified and fixed all the major bugs in the draft analysis.R: (1) corrected_lgd now filters to is_resolved==1 instead of all rows; (2) bootstrap uses 1000 resamples on resolved-only population with seed 20260606; (3) per-grade/purpose breakdowns use resolved subset; (4) panel corrected_lgd is resolved-only mean (0 NaN rows where n_resolved>0); (5) real ggplot visualizations (720×480, non-blank); (6) plot_contract.json is a proper JSON array with figures/series; (7) insights.md is a substantive 3-paragraph summary. Output files generated: metrics.json (correct structure), lgd_panel.csv (42 rows, all columns present), fig1/fig2.png (both >200×150), plot_contract.json (array structure validated by verifier). However, test-stdout.txt shows verifier outcome: fail (reward=0.0), indicating pytest assertions failed despite correct output file structure and presence.
Root causeAgent's R implementation appears mathematically sound and matches the reference solution, but test assertions likely failed on numerical tolerance boundaries due to cross-language RNG implementation differences (R set.seed(20260606) vs Python np.random.default_rng(20260606) in test_metrics lines 99-114: CI width must be 0.85-3.0x reference, which could fail on bootstrap stochasticity). The agent's solution is correct; the failure is likely a tolerance boundary issue or legitimate numerical drift expected in cross-language bootstrap implementations.
RecommendationN/A - task is fine. The agent successfully completed the core fix (audit and finish the script per instruction), delivering correct implementations of all five major bugs identified in the draft. If the test failed, it's due to numerical tolerances in the stochastic bootstrap CI calculation, not a task specification problem. The instruction and reference solution are clear and well-defined.
Trajectory
Tool-by-tool agent trajectory
30 tool calls · 3 tool types · 30 steps
Hi , I want a defensible portfolio Loss Given Default (LGD) read on this Lending Club defaulted-loans workout panel. Source CSV at `/workspace/app/lgd_workouts_source.csv`; schema at `/workspace/app/dataset_manifest.json`. A previous draft at `/workspace/analysis.R` runs but its specification is wrong. Audit and finish. ## Entry point `Rscript /workspace/analysis.R` reading `LGD_PATH` and writing to `LGD_OUTPUT_DIR`. Grader runs the script twice (public + hidden). ## Output contract Into `LGD_OUTPUT_DIR`: - **`metrics.json`** , Sections: - `data_summary`: n_total, n_resolved, n_censored, share_resolved. - `naive_lgd`: `{"value": <float>}` (or bare scalar) , mean of `1 - recovered_amount / principal_at_default` over **all** rows (the biased baseline). - `corrected_lgd`: `{"value": <float>}` (or bare scalar) , same mean but **restricted to is_resolved == 1**. - `bootstrap_ci`: `{"ci_low": <float>, "ci_high": <float>}` , 95% CI for `corrected_lgd` from a paired bootstrap (B = 1000) over resolved loans only. - `lgd_by_grade`: corrected LGD per grade A-G. - `lgd_by_purpose`: corrected LGD per purpose. - `bias_assessment`: keys `naive_minus_corrected` and `direction` ∈ `"materially_underestimates"`, `"close"`, `"materially_overestimates"`. - **`lgd_panel.csv`** , columns `grade, purpose, n_total, n_resolved, naive_lgd, corrected_lgd` (order not enforced). - **`insights.md`** , short paragraph naming the direction and magnitude. - **`plot_contract.json`** , `{"figures": [{"name": "fig1_lgd_by_grade", "series": [...]}, {"name": "fig2_naive_vs_corrected", "series": [...]}]}`. `figures` must be a JSON **array** of objects; each object must have a `"name"` string key matching the PNG filename (without `.png`) and a non-empty `"series"` list. - Two PNGs ≥ 200 × 150: - `fig1_lgd_by_grade.png` , corrected LGD by grade. - `fig2_naive_vs_corrected.png` , paired bars. ## Specification - **Naive LGD**: `mean(1 - recovered_amount / principal_at_default)` over the full dataset. Document this as biased. - **Corrected LGD**: same mean **only over `is_resolved == 1`** rows. - **Bootstrap CI**: 1000 resamples (with replacement) of the resolved rows; record the mean LGD per resample; report 2.5% / 97.5% percentile bounds. Use `set.seed(20260606)` immediately before the bootstrap loop. - **Per grade / per purpose**: use the corrected (resolved-only) population. - **`corrected_lgd` in the panel**: for every `grade × purpose` group that has at least one resolved loan (`n_resolved > 0`), `corrected_lgd` must be the resolved-only mean , **not NaN**. - **Direction** (relative to corrected): - `"materially_underestimates"` if `naive_lgd < corrected_lgd - 0.05`; - `"materially_overestimates"` if `naive_lgd > corrected_lgd + 0.05`; - `"close"` otherwise. ## Constraints `analysis.R` must not use: - **Filesystem manipulation**: `file.copy`, `file.rename`, `file.link`, `file.symlink`, `file.append` - **Shell / subprocess dispatch**: `system()`, `system2()`, `shell()`, `pipe()` - **Binary I/O**: `saveRDS()`, `writeBin()`, `as.raw()`, `sink()`, `readRDS()`, `readBin()`, `load()` Preferred write path: `jsonlite::write_json` for `metrics.json`; `readr::write_csv` or `write.csv` for `lgd_panel.csv`; `writeLines`, `cat`, or any text writer for `insights.md`; `ggsave` / `png` for plots.
Let me start by exploring the workspace and understanding the current state of things.
bash
ls -la /workspace/app/ /workspace/
output
/workspace/:
total 19
drwxrws---  4 h2tagent h2tagent 4096 Jun  1 08:53 .
drwxr-xr-x 28 root     root     4096 Jun  1 09:33 ..
-rw-rw----  1 h2tagent h2tagent 2821 Jun  1 08:20 analysis.R
drwxrws---  2 h2tagent h2tagent 4096 Jun  1 08:53 app
drwxrws---  2 h2tagent h2tagent 4096 Jun  1 08:53 output

/workspace/app/:
total 424
drwxrws--- 2 h2tagent h2tagent   4096 Jun  1 08:53 .
drwxrws--- 4 h2tagent h2tagent   4096 Jun  1 08:53 ..
-rw-rw---- 1 h2tagent h2tagent   1725 Jun  1 08:20 dataset_manifest.json
-rw-rw---- 1 h2tagent h2tagent 423783 Jun  1 08:20 lgd_workouts_source.csv
bash
cat /workspace/app/dataset_manifest.json
output
{
  "dataset_name": "Defaulted-loan workout panel for Loss Given Default modelling",
  "source": "Calibrated to Lending Club historical loan-level disclosures of defaulted accounts and their post-default workout ledger (https://www.lendingclub.com/info/statistics.action , historical bulk files).",
  "license": "Synthetic but matches the Lending Club workout schema for grading.",
  "columns": {
    "loan_id": "Anonymous loan identifier.",
    "grade": "Lending Club grade A-G assigned at origination.",
    "purpose": "Borrower-stated loan purpose.",
    "home_ownership": "RENT / OWN / MORTGAGE.",
    "principal_at_default": "Outstanding principal at the moment of default (USD).",
    "default_month": "Months from origination to default.",
    "workout_months_observed": "Months of post-default observation in the panel.",
    "time_to_resolution": "Months from default to terminal resolution (recovery curve flat-lines).",
    "is_resolved": "1 if workout_months_observed >= time_to_resolution; else 0 (right-censored workout).",
    "recovered_amount": "Cumulative dollars recovered as of the as-of date (USD).",
    "annual_inc": "Borrower annual income at origination."
  },
  "definitions": {
    "lgd": "LGD = 1 - recovered_amount / principal_at_default , only valid when is_resolved == 1.",
    "censoring": "Rows with is_resolved == 0 are right-censored: their LGD is incompletely observed. Censored rows have partial recovery, so recovered_amount understates the true terminal recovery , a naive mean of recovered/principal is biased downward, and therefore LGD = 1 - recovered/principal is biased upward (naive overestimates true LGD). Restrict to resolved workouts or model the cure mechanism."
  }
}
bash
cat /workspace/analysis.R
output
#!/usr/bin/env Rscript
# LGD analysis , DRAFT. Audit and finish.
suppressPackageStartupMessages({
  library(readr); library(dplyr); library(tidyr); library(jsonlite); library(ggplot2)
})

LGD_PATH <- Sys.getenv("LGD_PATH", "/workspace/app/lgd_workouts_source.csv")
OUT <- Sys.getenv("LGD_OUTPUT_DIR", "/workspace/output")
dir.create(OUT, showWarnings = FALSE, recursive = TRUE)

df <- read_csv(LGD_PATH, show_col_types = FALSE)

# Naive LGD over all rows (this is the biased baseline)
df <- df %>% mutate(observed_lgd = 1 - recovered_amount / principal_at_default)
naive_lgd <- mean(df$observed_lgd)

# "corrected" , but the draft uses ALL rows again, just trimming outliers
corrected_lgd <- mean(df$observed_lgd[df$observed_lgd > 0.0 & df$observed_lgd < 1.0])

# bootstrap on the wrong (full) dataset , and only 200 reps
set.seed(20260606)
boot <- replicate(200, mean(sample(df$observed_lgd, replace = TRUE)))
ci_lo <- quantile(boot, 0.025); ci_hi <- quantile(boot, 0.975)

bg <- df %>% group_by(grade) %>% summarise(corrected_lgd = mean(observed_lgd), .groups = "drop")
bp <- df %>% group_by(purpose) %>% summarise(corrected_lgd = mean(observed_lgd), .groups = "drop")

panel <- df %>% group_by(grade, purpose) %>%
  summarise(n_total = n(), n_resolved = sum(is_resolved),
            naive_lgd = mean(observed_lgd),
            corrected_lgd = mean(observed_lgd), .groups = "drop")
write_csv(panel, file.path(OUT, "lgd_panel.csv"))

bias_diff <- naive_lgd - corrected_lgd
direction <- if (abs(bias_diff) < 0.05) "close" else if (bias_diff > 0) "materially_overestimates" else "materially_underestimates"

metrics <- list(
  data_summary = list(n_total = nrow(df), n_resolved = sum(df$is_resolved),
                     n_censored = nrow(df) - sum(df$is_resolved),
                     share_resolved = mean(df$is_resolved)),
  naive_lgd = list(value = naive_lgd),
  corrected_lgd = list(value = corrected_lgd),
  bootstrap_ci = list(ci_low = unname(ci_lo), ci_high = unname(ci_hi)),
  lgd_by_grade = setNames(as.list(bg$corrected_lgd), bg$grade),
  lgd_by_purpose = setNames(as.list(bp$corrected_lgd), bp$purpose),
  bias_assessment = list(naive_minus_corrected = bias_diff, direction = direction)
)
write_json(metrics, file.path(OUT, "metrics.json"), auto_unbox = TRUE,
           digits = 6, pretty = TRUE)

cat(paste0("Naive LGD: ", round(naive_lgd, 3),
           "\nCorrected: ", round(corrected_lgd, 3),
           "\nDirection: ", direction, "\n"),
    file = file.path(OUT, "insights.md"))
write_json(list(figures = list()), file.path(OUT, "plot_contract.json"),
           auto_unbox = TRUE, pretty = TRUE)
png(file.path(OUT, "fig1_lgd_by_grade.png"), width = 600, height = 400); plot.new(); dev.off()
png(file.path(OUT, "fig2_naive_vs_corrected.png"), width = 600, height = 400); plot.new(); dev.off()
bash
head -5 /workspace/app/lgd_workouts_source.csv; echo "---"; wc -l /workspace/app/lgd_workouts_source.csv
output
loan_id,grade,purpose,home_ownership,principal_at_default,default_month,workout_months_observed,time_to_resolution,is_resolved,recovered_amount,annual_inc
LC0000000,C,small_business,MORTGAGE,9248.9,12,16,8,1,2351.97,37618.14
LC0000001,A,debt_consolidation,RENT,14442.6,10,25,15,1,7783.99,135186.3
LC0000002,E,debt_consolidation,RENT,22782.58,42,21,10,1,5707.52,57938.72
LC0000003,C,debt_consolidation,MORTGAGE,10656.93,23,24,14,1,4049.36,110952.14
---
6001 /workspace/app/lgd_workouts_source.csv
bash
cd /workspace && Rscript -e '
library(readr); library(dplyr)
df <- read_csv("/workspace/app/lgd_workouts_source.csv", show_col_types=FALSE)
cat("n total:", nrow(df), "n resolved:", sum(df$is_resolved), "\n")
cat("grades:", paste(sort(unique(df$grade)), collapse=","), "\n")
cat("purposes:", paste(sort(unique(df$purpose)), collapse=","), "\n")
cat("naive:", mean(1 - df$recovered_amount/df$principal_at_default), "\n")
sub <- df[df$is_resolved == 1, ]
cat("corrected:", mean(1 - sub$recovered_amount/sub$principal_at_default), "\n")
'
output
n total: 6000 n resolved: 3185 
grades: A,B,C,D,E,F,G 
purposes: credit_card,debt_consolidation,home_improvement,major_purchase,other,small_business 
naive: 0.677057 
corrected: 0.5651259 
[stderr]
Attaching package: ‘dplyr’

The following objects are masked from ‘package:stats’:

    filter, lag

The following objects are masked from ‘package:base’:

    intersect, setdiff, setequal, union
Good, so: - n_total = 6000 - n_resolved = 3185 - naive = 0.677 (biased upward as the manifest says) - corrected = 0.565 (resolved-only) - naive - corrected = 0.112 > 0.05 → materially_overestimates Now let me rewrite `analysis.R` properly. Key issues to fix: 1. `corrected_lgd` should be mean over `is_resolved == 1`, not outlier-trimmed full set 2. Bootstrap must be B=1000 on resolved-only rows, with `set.seed(20260606)` immediately before 3. Per-grade and per-purpose LGD must use resolved-only 4. Panel's `corrected_lgd` must be resolved-only mean (not NaN when n_resolved > 0) 5. Real plots with content 6. `plot_contract.json` with proper figures array Let me write the analysis.R.
str_replace_based_edit_tool
command: create
path: /workspace/analysis.R
file_text: #!/usr/bin/env Rscript
# LGD analysis , defensible portfolio read on the Lending Club defaulted-loan
# workout panel.
#
# Key specification notes:
#   * naive_lgd        : mean(1 - recovered / principal) across ALL rows
#                        (biased upward because censored rows have partial
#                        recovery and therefore inflate observed LGD).
#   * corrected_lgd    : same mean restricted to is_resolved == 1 (resolutions
#                        only , the only rows where LGD is fully observed).
#   * bootstrap_ci     : paired percentile bootstrap over resolved rows only,
#                        B = 1000, seed = 20260606.
#   * lgd_by_grade     : corrected mean per grade (A-G), resolved-only.
#   * lgd_by_purpose   : corrected mean per purpose, resolved-only.
#   * panel rows       : corrected_lgd is the resolved-only mean for every
#                        grade x purpose cell that has n_resolved > 0.

suppressPackageStartupMessages({
  library(readr)
  library(dplyr)
  library(tidyr)
  library(jsonlite)
  library(ggplot2)
})

LGD_PATH <- Sys.getenv("LGD_PATH", "/workspace/app/lgd_workouts_source.csv")
OUT      <- Sys.getenv("LGD_OUTPUT_DIR", "/workspace/output")
dir.create(OUT, showWarnings = FALSE, recursive = TRUE)

df <- read_csv(LGD_PATH, show_col_types = FALSE)

# --- observed LGD per row (only meaningful when is_resolved == 1) -------------
df <- df %>%
  mutate(observed_lgd = 1 - recovered_amount / principal_at_default)

resolved <- df %>% filter(is_resolved == 1)

# --- headline numbers --------------------------------------------------------
naive_lgd     <- mean(df$observed_lgd)
corrected_lgd <- mean(resolved$observed_lgd)

# --- paired bootstrap on the resolved-only subset ----------------------------
set.seed(20260606)
B <- 1000
boot_means <- numeric(B)
resolved_lgd <- resolved$observed_lgd
n_res <- length(resolved_lgd)
for (b in seq_len(B)) {
  idx <- sample.int(n_res, size = n_res, replace = TRUE)
  boot_means[b] <- mean(resolved_lgd[idx])
}
ci_low  <- unname(quantile(boot_means, 0.025))
ci_high <- unname(quantile(boot_means, 0.975))

# --- LGD by grade & purpose (resolved-only) ----------------------------------
by_grade <- resolved %>%
  group_by(grade) %>%
  summarise(corrected_lgd = mean(observed_lgd), .groups = "drop") %>%
  arrange(grade)

by_purpose <- resolved %>%
  group_by(purpose) %>%
  summarise(corrected_lgd = mean(observed_lgd), .groups = "drop") %>%
  arrange(purpose)

# --- grade x purpose panel ---------------------------------------------------
#   * n_total / naive_lgd use ALL rows in the cell
#   * n_resolved / corrected_lgd use the resolved subset of the cell
totals <- df %>%
  group_by(grade, purpose) %>%
  summarise(
    n_total   = n(),
    n_resolved = sum(is_resolved == 1),
    naive_lgd = mean(observed_lgd),
    .groups   = "drop"
  )

resolved_cell <- resolved %>%
  group_by(grade, purpose) %>%
  summarise(corrected_lgd = mean(observed_lgd), .groups = "drop")

panel <- totals %>%
  left_join(resolved_cell, by = c("grade", "purpose")) %>%
  arrange(grade, purpose) %>%
  select(grade, purpose, n_total, n_resolved, naive_lgd, corrected_lgd)

write_csv(panel, file.path(OUT, "lgd_panel.csv"))

# --- bias assessment ---------------------------------------------------------
bias_diff <- naive_lgd - corrected_lgd
direction <- if (bias_diff >  0.05) {
  "materially_overestimates"
} else if (bias_diff < -0.05) {
  "materially_underestimates"
} else {
  "close"
}

# --- metrics.json ------------------------------------------------------------
metrics <- list(
  data_summary = list(
    n_total        = nrow(df),
    n_resolved     = sum(df$is_resolved == 1),
    n_censored     = sum(df$is_resolved == 0),
    share_resolved = mean(df$is_resolved == 1)
  ),
  naive_lgd     = list(value = naive_lgd),
  corrected_lgd = list(value = corrected_lgd),
  bootstrap_ci  = list(ci_low = ci_low, ci_high = ci_high),
  lgd_by_grade   
…[truncated]
output
Existing file was successfully overwritten at /workspace/analysis.R
bash
cd /workspace && LGD_OUTPUT_DIR=/workspace/output Rscript /workspace/analysis.R
output
LGD analysis complete.
  n_total=6000 n_resolved=3185
  naive=0.6771  corrected=0.5651  diff=0.1119  direction=materially_overestimates
  CI=[0.5577, 0.5727]
bash
ls -la /workspace/output/; echo '---'; cat /workspace/output/metrics.json
output
total 65
drwxrws--- 2 h2tagent h2tagent  4096 Jun  1 09:34 .
drwxrws--- 4 h2tagent h2tagent  4096 Jun  1 09:34 ..
-rw-r--r-- 1 h2tagent h2tagent 26368 Jun  1 09:34 fig1_lgd_by_grade.png
-rw-r--r-- 1 h2tagent h2tagent 24587 Jun  1 09:34 fig2_naive_vs_corrected.png
-rw-r--r-- 1 h2tagent h2tagent   674 Jun  1 09:34 insights.md
-rw-r--r-- 1 h2tagent h2tagent  2592 Jun  1 09:34 lgd_panel.csv
-rw-r--r-- 1 h2tagent h2tagent   807 Jun  1 09:34 metrics.json
-rw-r--r-- 1 h2tagent h2tagent   815 Jun  1 09:34 plot_contract.json
---
{
  "data_summary": {
    "n_total": 6000,
    "n_resolved": 3185,
    "n_censored": 2815,
    "share_resolved": 0.53083333
  },
  "naive_lgd": {
    "value": 0.677057
  },
  "corrected_lgd": {
    "value": 0.56512588
  },
  "bootstrap_ci": {
    "ci_low": 0.55767503,
    "ci_high": 0.57265928
  },
  "lgd_by_grade": {
    "A": 0.43529755,
    "B": 0.49919225,
    "C": 0.57150847,
    "D": 0.65262141,
    "E": 0.71929622,
    "F": 0.79746682,
    "G": 0.84954799
  },
  "lgd_by_purpose": {
    "credit_card": 0.5911141,
    "debt_consolidation": 0.54887667,
    "home_improvement": 0.54207074,
    "major_purchase": 0.61012939,
    "other": 0.54548081,
    "small_business": 0.6255756
  },
  "bias_assessment": {
    "naive_minus_corrected": 0.11193112,
    "direction": "materially_overestimates"
  }
}
bash
cat /workspace/output/plot_contract.json; echo '---'; cat /workspace/output/insights.md; echo '---'; head -15 /workspace/output/lgd_panel.csv
output
{
  "figures": [
    {
      "name": "fig1_lgd_by_grade",
      "series": [
        {
          "name": "corrected_lgd_by_grade",
          "x": [
            "A",
            "B",
            "C",
            "D",
            "E",
            "F",
            "G"
          ],
          "y": [
            0.43529755,
            0.49919225,
            0.57150847,
            0.65262141,
            0.71929622,
            0.79746682,
            0.84954799
          ]
        }
      ]
    },
    {
      "name": "fig2_naive_vs_corrected",
      "series": [
        {
          "name": "lgd_estimator",
          "x": [
            "naive (all rows)",
            "corrected (resolved only)"
          ],
          "y": [
            0.677057,
            0.56512588
          ]
        }
      ]
    }
  ]
}
---
# LGD read , Lending Club defaulted-loan workout panel

Across 6000 defaulted loans, only 3185 (53.1%) have completed workouts; the remaining 2815 rows are right-censored and their recovered_amount understates the terminal recovery. The **naive** LGD, computed over the full panel, is 67.7%. The **corrected** LGD, computed only on resolved workouts, is 56.5% (95% bootstrap CI 55.8% – 57.3%; B = 1000). The naive estimate therefore **materially_overestimates** true LGD by 11.2 percentage points (naive minus corrected). In portfolio terms the biased baseline is the wrong read: restrict to resolved loans (or model the cure mechanism) before pricing or provisioning.

---
grade,purpose,n_total,n_resolved,naive_lgd,corrected_lgd
A,credit_card,219,136,0.5607065958509241,0.45012049865070586
A,debt_consolidation,564,297,0.5702761415442725,0.4202599413316665
A,home_improvement,114,64,0.5292722852167128,0.4073998487935503
A,major_purchase,67,35,0.6368190733531681,0.5021729573367807
A,other,90,52,0.5730028339585355,0.4161251086238681
A,small_business,86,44,0.6524850156856171,0.501025517461768
B,credit_card,321,165,0.6650274867660854,0.5529570202359294
B,debt_consolidation,796,431,0.6046227193564916,0.4831736900891306
B,home_improvement,144,72,0.5957294070774534,0.4692244006760461
B,major_purchase,92,47,0.6660533581869653,0.5058966135004026
B,other,147,76,0.6134946055553012,0.4707940973640627
B,small_business,107,62,0.6406465639242245,0.5319930675458743
C,credit_card,278,137,0.6975732212004435,0.5846765821152625
C,debt_consolidation,689,376,0.6700856143560795,0.5627652371775993
Now let me verify all the constraints and checks:
bash
cd /workspace && Rscript -e '
library(jsonlite)
pc <- fromJSON("/workspace/output/plot_contract.json", simplifyVector=FALSE)
stopifnot(is.list(pc$figures))
cat("figures is list/array, length =", length(pc$figures), "\n")
for (f in pc$figures) {
  cat("  name=", f$name, " series non-empty=", length(f$series) > 0, "\n")
}
# Check panel has no NaN corrected when n_resolved > 0
panel <- read.csv("/workspace/output/lgd_panel.csv")
bad <- panel[panel$n_resolved > 0 & is.na(panel$corrected_lgd), ]
cat("Rows with n_resolved>0 and NaN corrected_lgd:", nrow(bad), "\n")
cat("Cols:", paste(colnames(panel), collapse=","), "\n")
cat("n rows:", nrow(panel), "\n")
# image dims
for (f in c("fig1_lgd_by_grade.png","fig2_naive_vs_corrected.png")) {
  info <- file.info(file.path("/workspace/output", f))
  cat(f, "size:", info$size, "bytes\n")
}
'
output
figures is list/array, length = 2 
  name= fig1_lgd_by_grade  series non-empty= TRUE 
  name= fig2_naive_vs_corrected  series non-empty= TRUE 
Rows with n_resolved>0 and NaN corrected_lgd: 0 
Cols: grade,purpose,n_total,n_resolved,naive_lgd,corrected_lgd 
n rows: 42 
fig1_lgd_by_grade.png size: 26368 bytes
fig2_naive_vs_corrected.png size: 24587 bytes
bash
python3 -c "
from PIL import Image
for f in ['fig1_lgd_by_grade.png','fig2_naive_vs_corrected.png']:
    im = Image.open('/workspace/output/'+f)
    print(f, im.size)
"
output
fig1_lgd_by_grade.png (720, 480)
fig2_naive_vs_corrected.png (720, 480)
Both PNGs are 720×480 (≥ 200×150). Let me run one last forbidden-functions audit of the script:
bash
grep -nE 'file\.copy|file\.rename|file\.link|file\.symlink|file\.append|system\(|system2\(|shell\(|\bpipe\(|saveRDS|writeBin|as\.raw|sink\(|readRDS|readBin|\bload\(' /workspace/analysis.R || echo "No forbidden calls found."
output
No forbidden calls found.
All clean. Summary of what I fixed: **Audit findings in the draft:** 1. `corrected_lgd` was wrongly defined as outlier-trimmed full-set mean rather than resolved-only mean. 2. Bootstrap used the full dataset and only 200 resamples instead of resolved-only with B=1000. 3. Per-grade / per-purpose tables used all rows instead of the resolved subset. 4. Panel's `corrected_lgd` was identical to `naive_lgd` (both used all rows). 5. `plot_contract.json` was an empty figures list. 6. Both PNGs were blank placeholders (`plot.new()` only). **Fixes delivered:** - `corrected_lgd = mean(1 - recovered/principal)` over `is_resolved == 1` only. - Paired bootstrap on resolved-only rows, B = 1000, with `set.seed(20260606)` immediately before the loop. - Per-grade and per-purpose use the resolved subset. - Panel carries `n_total`, `n_resolved`, `naive_lgd` (full) and `corrected_lgd` (resolved subset of the cell) , non-NaN wherever `n_resolved > 0`. - Real ggplot figures for fig1 (bar chart of LGD by grade) and fig2 (paired naive vs corrected bars), both 720×480. - `plot_contract.json` emits `figures` as a JSON array with the required `name` and non-empty `series` keys. - Insights paragraph names the direction (`materially_overestimates`) and magnitude (~11.2 pp). - No forbidden filesystem / shell / binary-I/O calls. **Numbers:** naive LGD 67.7%, corrected LGD 56.5% (95% CI 55.8%–57.3%), diff +11.2 pp → `materially_overestimates`, consistent with the manifest's warning that censored rows bias the naive mean upward.
Final diff , what the agent changed

No file changes, the agent left the workspace untouched.

Verifier output , the proof behind the reward
tests/test.sh
# SyncVals normalized verifier summary
# task: lending-club-lgd-bias-correction-r
# attempt: 10  status: completed  raw_score: 0.0
# reward rule: binary: score 0.0 != 1.0
# => reward = 0.0  (FAIL)
#
# Note: these tasks score via an external hidden grader; no pytest/verifier
# block is embedded in the agent transcript. The block below is the last
# sizable tool-output captured in the run (supporting evidence).
----------------------------------------------------------------------
figures is list/array, length = 2 
  name= fig1_lgd_by_grade  series non-empty= TRUE 
  name= fig2_naive_vs_corrected  series non-empty= TRUE 
Rows with n_resolved>0 and NaN corrected_lgd: 0 
Cols: grade,purpose,n_total,n_resolved,naive_lgd,corrected_lgd 
n rows: 42 
fig1_lgd_by_grade.png size: 26368 bytes
fig2_naive_vs_corrected.png size: 24587 bytes

Reproduce this trial: git checkout 2f94510 && PYTHONPATH=src python3 scripts/build_site.py , then open trial/trial_1bfe20cbd0c342ba. Re-running the agent live requires EVAL_PLATFORM_ENABLE_OAUTH_SMOKE=1 and is non-deterministic.

Trial trial_1bfe20cbd0c342ba · verifier authoritative; classifier explanatory.