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What Should This Camera Cost?

From its release year, resolution, zoom, focus range, storage, weight and size, what price does this camera's spec suggest? Buyers use a fair-price estimate to spot bargains and overpriced stock.

Use caseCustomersPredictionModel evaluation

The table

1,038 camera models with release year, resolution, zoom, focus range, storage, weight and dimensions, and their price. It's in Welt's research catalogue as 1000 Cameras Dataset, 1,038 rows by 13 columns, licensed CC BY-SA 3.0. The catalogue measures its signal at 0.52. At 1,038 rows and 12 features, TabICLv2, Kumo Tabular Medium and Mitra-v2 take the table as it is. The others can't take a table this size, so the walkthrough leaves them out.

Walkthrough

  1. Load it from the catalogue

    Find the table, read its recorded target and print the column names.

    import pandas as pd
    from welt import Client
    
    with Client() as client:
        item = client.research_datasets(q="1000 cameras", limit=1)["items"][0]
        info = client.research_dataset(item["id"])
        data = client.load_research_dataset(item["id"])
    
    target = info["targets"][0]
    target = target["name"] if isinstance(target, dict) else target
    print([column["name"] for column in info["schema"]], target)
  2. Pick the rows

    Set aside 20 rows to predict at the end, and keep the rest for the models to learn from.

    known = data.dropna(subset=[target])
    new_rows = known.sample(20, random_state=1)
    table = known.drop(new_rows.index)
  3. Compare the models and predict

    The models compete on the same folds against a simple guess, then the top-ranked one is fitted on the whole table. RMSE and MAE are average errors in the target's own units, so lower is better. The last table puts each prediction next to the real answer.

    with Client() as client:
        evaluation = client.evaluate(table, target, task="regression", seed=7,
                                     models=["tabicl-v2", "kumo-medium", "mitra-v2"])
        model = evaluation.fit()
    
    print(evaluation.summary()[["name", "rank", "rmse_mean", "mae_mean"]])
    features = new_rows.drop(columns=target)
    print(pd.DataFrame({"actual": new_rows[target].values, "predicted": model.predict(features)}))

What you get

A fair priceFor any camera spec.
Over- and under-priced modelsCompare the estimate with the list price.
Small data handledAbout a thousand rows fit without sampling.

Try it

Use Open with to run the research datasets notebook in Colab, Kaggle or Jupyter and search for "1000 cameras", or run the code above after pip install "welt-client[parquet]".