{
 "record_id": "a7a83b631f85316bae926a6c965b325fb26c01c4",
 "eligible": true,
 "exclusion_reason": null,
 "study": {
  "title": "A gamma generalised linear model as an alternative to log linear real estate price functions",
  "year": 2019,
  "doi": "10.4102/jef.v12i1.476",
  "country": "South Africa",
  "region_city": "national (all provinces)",
  "sample_start": 2013,
  "sample_end": 2017,
  "property_type": "mixed",
  "price_type": "listing",
  "data_source": "online residential property portal aggregating agency listings (415 200 listings after cleaning)",
  "document_type": "journal",
  "estimators": [
   "other"
  ],
  "spatial_method": "submarket (area/suburb) factor dummies; Moran's I permutation test on residuals",
  "time_fe": false,
  "location_fe": true,
  "se_type": "unknown",
  "n_obs_total": 415200,
  "ai_methods": [
   "autoencoder (H2O) used only for anomaly detection in data cleaning"
  ],
  "notes": "Journal of Economic and Financial Sciences 12(1) a476. Separate cross-sectional gamma GLM (log link) per year 2013-2017; 70/30 train/holdout split. Normal and lognormal GLM alternatives estimated but their coefficients are not tabulated. Property types: apartment (reference), cluster, duplex, house, simplex, townhouse. Lot size excluded from models."
 },
 "models": [
  {
   "model_id": "T4-2013",
   "table": "4",
   "column": "2013",
   "page": 9,
   "dep_var": "Listing price (ZAR)",
   "dep_transform": "other",
   "estimator": "other",
   "n_obs": null,
   "r2": null,
   "se_or_t_in_parentheses": "p",
   "sample_subset": "listings advertised in 2013; 70% training split",
   "notes": "Gamma GLM with log link (dependent on original scale, coefficients interpreted by authors as percentage effects, beta*100). Table 4 reports beta-hat and p-value only (no SE). Per-year n not printed; total final data set 415 200 listings (2013-2017), 70% used for training. Deviance explained D2=0.89 (Table 3, p.5). Area (suburb) factor with >2000 levels included as location control, coefficients not reported."
  },
  {
   "model_id": "T4-2014",
   "table": "4",
   "column": "2014",
   "page": 9,
   "dep_var": "Listing price (ZAR)",
   "dep_transform": "other",
   "estimator": "other",
   "n_obs": null,
   "r2": null,
   "se_or_t_in_parentheses": "p",
   "sample_subset": "listings advertised in 2014; 70% training split",
   "notes": "Gamma GLM with log link (dependent on original scale, coefficients interpreted by authors as percentage effects, beta*100). Table 4 reports beta-hat and p-value only (no SE). Per-year n not printed; total final data set 415 200 listings (2013-2017), 70% used for training. Deviance explained D2=0.87 (Table 3, p.5). Area (suburb) factor with >2000 levels included as location control, coefficients not reported."
  },
  {
   "model_id": "T4-2015",
   "table": "4",
   "column": "2015",
   "page": 9,
   "dep_var": "Listing price (ZAR)",
   "dep_transform": "other",
   "estimator": "other",
   "n_obs": null,
   "r2": null,
   "se_or_t_in_parentheses": "p",
   "sample_subset": "listings advertised in 2015; 70% training split",
   "notes": "Gamma GLM with log link (dependent on original scale, coefficients interpreted by authors as percentage effects, beta*100). Table 4 reports beta-hat and p-value only (no SE). Per-year n not printed; total final data set 415 200 listings (2013-2017), 70% used for training. Deviance explained D2=0.87 (Table 3, p.5). Area (suburb) factor with >2000 levels included as location control, coefficients not reported."
  },
  {
   "model_id": "T4-2016",
   "table": "4",
   "column": "2016",
   "page": 9,
   "dep_var": "Listing price (ZAR)",
   "dep_transform": "other",
   "estimator": "other",
   "n_obs": null,
   "r2": null,
   "se_or_t_in_parentheses": "p",
   "sample_subset": "listings advertised in 2016; 70% training split",
   "notes": "Gamma GLM with log link (dependent on original scale, coefficients interpreted by authors as percentage effects, beta*100). Table 4 reports beta-hat and p-value only (no SE). Per-year n not printed; total final data set 415 200 listings (2013-2017), 70% used for training. Deviance explained D2=0.87 (Table 3, p.5). Area (suburb) factor with >2000 levels included as location control, coefficients not reported."
  },
  {
   "model_id": "T4-2017",
   "table": "4",
   "column": "2017",
   "page": 9,
   "dep_var": "Listing price (ZAR)",
   "dep_transform": "other",
   "estimator": "other",
   "n_obs": null,
   "r2": null,
   "se_or_t_in_parentheses": "p",
   "sample_subset": "listings advertised in 2017; 70% training split",
   "notes": "Gamma GLM with log link (dependent on original scale, coefficients interpreted by authors as percentage effects, beta*100). Table 4 reports beta-hat and p-value only (no SE). Per-year n not printed; total final data set 415 200 listings (2013-2017), 70% used for training. Deviance explained D2=0.88 (Table 3, p.5). Area (suburb) factor with >2000 levels included as location control, coefficients not reported."
  }
 ],
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   "t": null,
   "p": 2e-09,
   "p_stars": "",
   "ci_lo": null,
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   "page": 9,
   "confidence": "high",
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   "ci_lo": null,
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   "page": 9,
   "confidence": "high",
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   "confidence": "high",
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   "page": 9,
   "confidence": "high",
   "notes": "property type dummy, reference = apartment"
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   "p_stars": "",
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   "page": 9,
   "confidence": "high",
   "notes": "property type dummy, reference = apartment"
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   "p_stars": "",
   "ci_lo": null,
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   "confidence": "high",
   "notes": "property type dummy, reference = apartment"
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   "var_name_printed": "Simplex",
   "taxonomy_id": "dwelling_type",
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   "ci_lo": null,
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   "page": 9,
   "confidence": "medium",
   "notes": "property type dummy, reference = apartment; p printed as '4-e5' (apparent typo for 4e-5)"
  },
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   "model_id": "T4-2013",
   "var_name_printed": "Townhouse",
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   "ci_lo": null,
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   "page": 9,
   "confidence": "high",
   "notes": "property type dummy, reference = apartment"
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   "var_name_printed": "Log (size)",
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   "page": 9,
   "confidence": "high",
   "notes": ""
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  {
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   "var_name_printed": "Bedrooms",
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   "ci_lo": null,
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   "page": 9,
   "confidence": "high",
   "notes": ""
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   "model_id": "T4-2014",
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   "page": 9,
   "confidence": "high",
   "notes": ""
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   "var_name_printed": "Cluster",
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   "page": 9,
   "confidence": "high",
   "notes": "property type dummy, reference = apartment"
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   "model_id": "T4-2014",
   "var_name_printed": "Duplex",
   "taxonomy_id": "dwelling_type",
   "x_transform": "dummy",
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   "page": 9,
   "confidence": "high",
   "notes": "property type dummy, reference = apartment"
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   "var_name_printed": "House",
   "taxonomy_id": "dwelling_type",
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   "page": 9,
   "confidence": "high",
   "notes": "property type dummy, reference = apartment"
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   "taxonomy_id": "dwelling_type",
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   "se": null,
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   "p_stars": "",
   "ci_lo": null,
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   "page": 9,
   "confidence": "high",
   "notes": "property type dummy, reference = apartment"
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   "model_id": "T4-2014",
   "var_name_printed": "Townhouse",
   "taxonomy_id": "dwelling_type",
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   "page": 9,
   "confidence": "high",
   "notes": "property type dummy, reference = apartment"
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   "var_name_printed": "Log (size)",
   "taxonomy_id": "living_area",
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   "p": 2e-09,
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   "page": 9,
   "confidence": "high",
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   "var_name_printed": "Bedrooms",
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   "confidence": "high",
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   "confidence": "high",
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   "confidence": "high",
   "notes": "property type dummy, reference = apartment"
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   "confidence": "high",
   "notes": "property type dummy, reference = apartment"
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   "confidence": "high",
   "notes": "property type dummy, reference = apartment"
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   "confidence": "high",
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   "confidence": "high",
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   "confidence": "high",
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   "confidence": "high",
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   "confidence": "high",
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   "confidence": "high",
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   "page": 9,
   "confidence": "high",
   "notes": "property type dummy, reference = apartment"
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   "confidence": "high",
   "notes": "property type dummy, reference = apartment"
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   "taxonomy_id": "dwelling_type",
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   "confidence": "high",
   "notes": "property type dummy, reference = apartment"
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   "taxonomy_id": "living_area",
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   "page": 9,
   "confidence": "high",
   "notes": ""
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   "page": 9,
   "confidence": "high",
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   "var_name_printed": "Bathrooms",
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   "confidence": "high",
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   "confidence": "high",
   "notes": "property type dummy, reference = apartment"
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   "var_name_printed": "Duplex",
   "taxonomy_id": "dwelling_type",
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   "page": 9,
   "confidence": "high",
   "notes": "property type dummy, reference = apartment"
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   "model_id": "T4-2017",
   "var_name_printed": "House",
   "taxonomy_id": "dwelling_type",
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   "page": 9,
   "confidence": "high",
   "notes": "property type dummy, reference = apartment"
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  {
   "model_id": "T4-2017",
   "var_name_printed": "Simplex",
   "taxonomy_id": "dwelling_type",
   "x_transform": "dummy",
   "x_unit": "binary",
   "beta": 0.087,
   "se": null,
   "t": null,
   "p": 2e-09,
   "p_stars": "",
   "ci_lo": null,
   "ci_hi": null,
   "page": 9,
   "confidence": "high",
   "notes": "property type dummy, reference = apartment"
  },
  {
   "model_id": "T4-2017",
   "var_name_printed": "Townhouse",
   "taxonomy_id": "dwelling_type",
   "x_transform": "dummy",
   "x_unit": "binary",
   "beta": 0.099,
   "se": null,
   "t": null,
   "p": 2e-09,
   "p_stars": "",
   "ci_lo": null,
   "ci_hi": null,
   "page": 9,
   "confidence": "high",
   "notes": "property type dummy, reference = apartment"
  }
 ]
}