From a4a56b9e0b8c1c49fb7e010ba14111d4072ca4bc Mon Sep 17 00:00:00 2001
From: Bart Arendarczyk <s1924442@ed.ac.uk>
Date: Fri, 13 Jan 2023 16:46:33 +0000
Subject: [PATCH] Improved price adjustment and stock level control.
---
src/ac/ed/lurg/InternationalMarket.java | 8 +--
src/ac/ed/lurg/ModelConfig.java | 5 +-
src/ac/ed/lurg/country/CountryAgent.java | 27 +++++++---
src/ac/ed/lurg/country/GlobalPrice.java | 62 ++++++++++++++++++-----
src/ac/ed/lurg/landuse/CropUsageData.java | 4 ++
src/ac/ed/lurg/types/CropType.java | 20 ++++----
6 files changed, 91 insertions(+), 35 deletions(-)
diff --git a/src/ac/ed/lurg/InternationalMarket.java b/src/ac/ed/lurg/InternationalMarket.java
index cb8be1b4..797c8eb6 100644
--- a/src/ac/ed/lurg/InternationalMarket.java
+++ b/src/ac/ed/lurg/InternationalMarket.java
@@ -141,7 +141,8 @@ public class InternationalMarket {
double imports = totalImportCommodities.containsKey(crop) ? totalImportCommodities.get(crop) : 0.0;
double exportsBeforeTransportLosses = totalExportCommodities.containsKey(crop) ? totalExportCommodities.get(crop) : 0.0;
LogWriter.println(timestep.getYear() + " Updating " + crop.getGamsName() + " prices", 2);
- GlobalPrice adjustedPrice = prevPrice.createWithUpdatedMarketPrices(imports, exportsBeforeTransportLosses, timestep, totalProduction.get(crop), true);
+ GlobalPrice adjustedPrice = prevPrice.createWithUpdatedMarketPrices(imports, exportsBeforeTransportLosses,
+ timestep, totalProduction.get(crop), true, crop.getStockToUseRatio());
LogWriter.println( String.format("Price for %s updated from %s to %s \n", crop.getGamsName(), prevPrice, adjustedPrice), 2);
if (adjustedPrice.getStockLevel() < 0)
LogWriter.println("Global stocks are below zero" + crop.getGamsName() + ", " + timestep.getYear(), 2);
@@ -167,7 +168,8 @@ public class InternationalMarket {
totalCarbonSequestered = Math.max(totalCarbonSequestered, 0.0000001); // avoid division by 0
GlobalPrice prevCPrice = carbonPrice;
LogWriter.println(timestep.getYear() + " Updating carbon price", 2);
- GlobalPrice adjustedCPrice = prevCPrice.createWithUpdatedMarketPrices(totalCarbonImport, totalCarbonExport, timestep, totalCarbonSequestered, false);
+ GlobalPrice adjustedCPrice = prevCPrice.createWithUpdatedMarketPrices(totalCarbonImport, totalCarbonExport, timestep,
+ totalCarbonSequestered, false, 0.2);
LogWriter.println( String.format("Price for carbon updated from %s to %s \n", prevCPrice, adjustedCPrice), 2);
if (adjustedCPrice.getStockLevel() < 0)
LogWriter.println("Global stocks are below zero carbon, " + timestep.getYear(), 2);
@@ -193,7 +195,7 @@ public class InternationalMarket {
GlobalPrice prevTPrice = woodPrices.get(woodType);
LogWriter.println(timestep.getYear() + " Updating " + woodType.getName() + " price", 2);
GlobalPrice adjustedTPrice = prevTPrice.createWithUpdatedMarketPrices(totalWoodImport, totalWoodExport,
- timestep, totalWoodProduction, true);
+ timestep, totalWoodProduction, true, 0.2);
LogWriter.println( String.format("Price for wood updated from %s to %s \n", prevTPrice, adjustedTPrice), 2);
if (adjustedTPrice.getStockLevel() < 0)
LogWriter.println("Global stocks are below zero wood, " + timestep.getYear(), 2);
diff --git a/src/ac/ed/lurg/ModelConfig.java b/src/ac/ed/lurg/ModelConfig.java
index 61b8b573..92f5e57c 100755
--- a/src/ac/ed/lurg/ModelConfig.java
+++ b/src/ac/ed/lurg/ModelConfig.java
@@ -417,8 +417,9 @@ public class ModelConfig {
public static final boolean RESET_ENERGYCROP_PRICE = getBooleanProperty("RESET_ENERGYCROP_PRICE", true); // Resets price after calibration to avoid problems due to low initial demand
// public static final double BIOENERGY_HEATING_VALUE_GJ_PER_T = getDoubleProperty("BIOENERGY_HEATING_VALUE_GJ_PER_T", 17.5); // GJ per t DM
- public static final double MARKET_LAMBA = getDoubleProperty("MARKET_LAMBA", 0.4); // controls international market price adjustment rate
- public static final boolean PRICE_UPDATE_BY_MARKET_IMBALANCE = getBooleanProperty("PRICE_UPDATE_BY_MARKET_IMBALANCE", false);;
+ public static final double MARKET_LAMBDA = getDoubleProperty("MARKET_LAMBA", 0.4); // controls international market price adjustment rate
+ public static final boolean PRICE_UPDATE_BY_MARKET_IMBALANCE = getBooleanProperty("PRICE_UPDATE_BY_MARKET_IMBALANCE", false);
+ public static final boolean PRICE_UPDATE_BY_STOCK_USE_RATIO = getBooleanProperty("PRICE_UPDATE_BY_STOCK_USE_RATIO", true);;
public static final double MAX_PRICE_INCREASE = getDoubleProperty("MAX_PRICE_INCREASE", 1.5);
public static final double MAX_PRICE_DECREASE = getDoubleProperty("MAX_PRICE_DECREASE", .75);
public static final int DEMAND_RECALC_MAX_ITERATIONS = IS_CALIBRATION_RUN ? 0 : getIntProperty("DEMAND_RECALC_MAX_ITERATIONS", 1); // 0 is original behaviour
diff --git a/src/ac/ed/lurg/country/CountryAgent.java b/src/ac/ed/lurg/country/CountryAgent.java
index 81d7aca6..625e3398 100644
--- a/src/ac/ed/lurg/country/CountryAgent.java
+++ b/src/ac/ed/lurg/country/CountryAgent.java
@@ -164,7 +164,7 @@ public class CountryAgent extends AbstractCountryAgent {
RasterSet<WoodYieldItem> woodYieldData, RasterSet<CarbonFluxItem> carbonFluxData, Map<LccKey, Double> conversionCosts) {
Map<CropType, TradeConstraint> importConstraints = new HashMap<CropType, TradeConstraint>();
- Map<CropType, Double> currentExportRestictions = (exportRestrictions == null) ? null : exportRestrictions.get(currentTimestep.getYear());
+ Map<CropType, Double> currentExportRestrictions = (exportRestrictions == null) ? null : exportRestrictions.get(currentTimestep.getYear());
for (Map.Entry<CropType, CropUsageData> entry : previousGamsRasterOutput.getCropUsageData().entrySet()) {
CropUsageData cropUsage = entry.getValue();
@@ -175,13 +175,28 @@ public class CountryAgent extends AbstractCountryAgent {
// max of supply overall, needed for when imports are supplying feed and change is zero to allow for production to replace imports
double maxOfProdOrSupply = cropUsage.getProductionExpected() + Math.max(baseTrade, 0); //max of supply for food
-
+ double production = cropUsage.getProductionExpected();
+ double netSupply = getCropUsageData().get(crop).getNetSupply();
+ GlobalPrice cropPrice = currentWorldPrices.get(crop);
+
if (ModelConfig.IS_CALIBRATION_RUN && currentTimestep.getTimestep() <= ModelConfig.END_FIRST_STAGE_CALIBRATION) {
changeUp = changeDown = 0;
} else {
if (crop.isImportedCrop()) {
- changeUp = maxOfProdOrSupply * currentWorldPrices.get(crop).getMaxImportChange();
- changeDown = maxOfProdOrSupply * currentWorldPrices.get(crop).getMaxExportChange();
+ // exporter or not fully reliant on exports. Avoid forcing import reliant countries to reduce imports
+ if (baseTrade < 0 || production > baseTrade) {
+ double tradeImbalanceFract = cropPrice.getTradeImbalanceFraction();
+ // If in danger of stocks becoming negative, shift towards more exports
+ if (cropPrice.isStockCritical()) {
+ baseTrade = baseTrade - Math.abs(baseTrade) * tradeImbalanceFract * 1.1;
+ changeUp = 0;
+ } else {
+ changeUp = maxOfProdOrSupply * ModelConfig.MAX_IMPORT_CHANGE;
+ }
+ } else {
+ changeUp = maxOfProdOrSupply * ModelConfig.MAX_IMPORT_CHANGE;
+ }
+ changeDown = maxOfProdOrSupply * ModelConfig.MAX_IMPORT_CHANGE;
}
}
@@ -190,8 +205,8 @@ public class CountryAgent extends AbstractCountryAgent {
}
double restiction = 0;
- if (currentExportRestictions != null) {
- Double r = currentExportRestictions.get(crop);
+ if (currentExportRestrictions != null) {
+ Double r = currentExportRestrictions.get(crop);
if (r != null)
restiction = r;
}
diff --git a/src/ac/ed/lurg/country/GlobalPrice.java b/src/ac/ed/lurg/country/GlobalPrice.java
index 8f9ee722..8d0d9067 100644
--- a/src/ac/ed/lurg/country/GlobalPrice.java
+++ b/src/ac/ed/lurg/country/GlobalPrice.java
@@ -16,12 +16,15 @@ public class GlobalPrice implements Serializable {
private double exportAmountBeforeLoss;
private double transportLosses;
private double stockLevel;
+ private double stockUseRatio;
private double referencePrice;
- private GlobalPrice(Timestep timestep, double exportPrice, double stockLevel, double importAmount, double exportAmountBeforeLoss, double transportLosses, double referencePrice) {
+ private GlobalPrice(Timestep timestep, double exportPrice, double stockLevel, double importAmount, double exportAmountBeforeLoss,
+ double transportLosses, double referencePrice, double stockUseRatio) {
this.timestep = timestep;
this.exportPrice = exportPrice;
this.stockLevel = stockLevel;
+ this.stockUseRatio = stockUseRatio;
this.importAmount = importAmount;
this.exportAmountBeforeLoss = exportAmountBeforeLoss;
this.transportLosses = transportLosses;
@@ -30,7 +33,8 @@ public class GlobalPrice implements Serializable {
}
public static GlobalPrice createInitial(double exportPrice, double intitalStock) {
- return new GlobalPrice(new Timestep(ModelConfig.START_TIMESTEP-1), exportPrice, intitalStock, Double.NaN, Double.NaN, Double.NaN, Double.NaN);
+ return new GlobalPrice(new Timestep(ModelConfig.START_TIMESTEP-1), exportPrice, intitalStock, Double.NaN,
+ Double.NaN, Double.NaN, Double.NaN, Double.NaN);
}
public double getExportPrice(){
@@ -68,7 +72,8 @@ public class GlobalPrice implements Serializable {
return transportLosses;
}
- public GlobalPrice createWithUpdatedMarketPrices(double newImports, double newExportAmountBeforeLoss, Timestep thisTimeStep, double production, boolean hasTransportLosses) {
+ public GlobalPrice createWithUpdatedMarketPrices(double newImports, double newExportAmountBeforeLoss, Timestep thisTimeStep,
+ double production, boolean hasTransportLosses, double targetStockUseRatio) {
if (newImports > 0 || newExportAmountBeforeLoss > 0) {
double oldDiff = timestep.equals(thisTimeStep) ? exportAmountBeforeLoss - transportLosses - importAmount : 0.0; // if recomputing for same year need to back our previous adjustment
@@ -81,6 +86,9 @@ public class GlobalPrice implements Serializable {
updatedStock = stockLevel; // don't update stock in inital stage of calibration
else
updatedStock = stockLevel + stockChange;
+
+ double targetStock = (production + newImports - newExportAmountBeforeLoss) * targetStockUseRatio;
+ double updatedStockUseRatio = production > 0 ? updatedStock / production : 0;
LogWriter.println(String.format(" imports %.2f, exports %.2f", newImports, newExportAmountBeforeLoss - newTransportLosses), 2);
LogWriter.println(String.format(" updatedStock %.2f, previous %.2f (last timestep %.2f), stockChange %.2f, oldDiff %.2f", updatedStock, stockLevel, stockLevel-oldDiff, stockChange, oldDiff), 2);
@@ -92,16 +100,27 @@ public class GlobalPrice implements Serializable {
}
else if (ModelConfig.PRICE_UPDATE_BY_MARKET_IMBALANCE) {
double ratio = stockChange/(production-stockChange);
- adjustment = Math.exp(-ratio * ModelConfig.MARKET_LAMBA);
+ adjustment = Math.exp(-ratio * ModelConfig.MARKET_LAMBDA);
LogWriter.println(String.format(" initally imbalance ratio= %.4f", ratio), 2);
}
+ else if (ModelConfig.PRICE_UPDATE_BY_STOCK_USE_RATIO) {
+ // If stock increasing and current stock above target stock : decrease price
+ // If stock decreasing and current stock below target stock : increase price
+ // Otherwise keep price constant to refill/deplete stock to reach target level
+ if ((stockChange > 0 && updatedStock > targetStock) || (stockChange < 0 && updatedStock < targetStock)) {
+ adjustment = 1 - ModelConfig.MARKET_LAMBDA * stockChange / targetStock;
+ } else {
+ adjustment = 1;
+ }
+ LogWriter.print(String.format(" initally adjustment= %.4f", adjustment), 2);
+ }
else {
if (stockChange == 0 && production == 0)
adjustment=1;
else if (stockChange >= 0) // stock increasing, so decrease price. stockChange is positive so adjustment < 1
- adjustment = 1 - ModelConfig.MARKET_LAMBA * stockChange/production;
+ adjustment = 1 - ModelConfig.MARKET_LAMBDA * stockChange/production;
else // stock decreasing, so increase price. stockChange is negative so adjustment > 1
- adjustment = 1 - ModelConfig.MARKET_LAMBA * stockChange/Math.max(0, stockLevel);
+ adjustment = 1 - ModelConfig.MARKET_LAMBDA * stockChange/Math.max(0, stockLevel);
LogWriter.print(String.format(" initally adjustment= %.4f", adjustment), 2);
}
@@ -117,7 +136,8 @@ public class GlobalPrice implements Serializable {
double newPrice = exportPrice * adjustment;
double refPrice = ModelConfig.IS_CALIBRATION_RUN ? exportPrice : referencePrice; // during calibration reference price isn't fixed, but it is after that
- return new GlobalPrice(thisTimeStep, newPrice, updatedStock, newImports, newExportAmountBeforeLoss, newTransportLosses, refPrice);
+ return new GlobalPrice(thisTimeStep, newPrice, updatedStock, newImports, newExportAmountBeforeLoss,
+ newTransportLosses, refPrice, updatedStockUseRatio);
}
else {
LogWriter.printlnError(String.format("Price for not updated (still %s), as no imports and no exports for it", exportPrice));
@@ -140,7 +160,8 @@ public class GlobalPrice implements Serializable {
}
public GlobalPrice createPriceAdjustedByFactor(double factor) {
- return new GlobalPrice(timestep, exportPrice * factor, stockLevel, importAmount, exportAmountBeforeLoss, transportLosses, referencePrice);
+ return new GlobalPrice(timestep, exportPrice * factor, stockLevel, importAmount, exportAmountBeforeLoss,
+ transportLosses, referencePrice, stockUseRatio);
}
public void resetStock(Double stock) {
@@ -158,14 +179,27 @@ public class GlobalPrice implements Serializable {
}
public double getMaxImportChange() {
- if (stockLevel <= 0) {
- return 0;
- } else {
- return calcTradeMaxChange(importAmount / exportAmountBeforeLoss);
- }
+ //return calcTradeMaxChange(importAmount / exportAmountBeforeLoss);
+ return stockLevel > importAmount ? Math.min(stockLevel / importAmount - 1, ModelConfig.MAX_IMPORT_CHANGE) : 0;
}
public double getMaxExportChange() {
- return calcTradeMaxChange(exportAmountBeforeLoss/ importAmount);
+ //return calcTradeMaxChange(exportAmountBeforeLoss/ importAmount);
+ return (exportAmountBeforeLoss > 1.2 * importAmount) ? 0 : ModelConfig.MAX_IMPORT_CHANGE;
+ }
+
+ public boolean isStockCritical() {
+ return stockLevel < importAmount && exportAmountBeforeLoss < importAmount * 1.2;
+ }
+
+ public double getTradeImbalanceFraction() {
+ double netImports = importAmount - exportAmountBeforeLoss;
+ double tradeVolume = importAmount + exportAmountBeforeLoss;
+ return netImports / tradeVolume;
}
+
+ public double getImportToExportRatio() {
+ return exportAmountBeforeLoss > 0 ? importAmount / exportAmountBeforeLoss : 0;
+ }
+
}
\ No newline at end of file
diff --git a/src/ac/ed/lurg/landuse/CropUsageData.java b/src/ac/ed/lurg/landuse/CropUsageData.java
index 2f42b7ee..9b371b6d 100644
--- a/src/ac/ed/lurg/landuse/CropUsageData.java
+++ b/src/ac/ed/lurg/landuse/CropUsageData.java
@@ -83,4 +83,8 @@ public class CropUsageData implements Serializable {
public double getArea(){
return area;
}
+
+ public double getNetSupply() {
+ return prod + netImportsExpected;
+ }
}
\ No newline at end of file
diff --git a/src/ac/ed/lurg/types/CropType.java b/src/ac/ed/lurg/types/CropType.java
index 3595e090..4441e9f7 100644
--- a/src/ac/ed/lurg/types/CropType.java
+++ b/src/ac/ed/lurg/types/CropType.java
@@ -11,18 +11,18 @@ import ac.ed.lurg.utils.LogWriter;
public enum CropType {
- WHEAT("WheatBarleyOats", "wheat", true, false, 9.5, ModelConfig.INITAL_PRICE_WHEAT, 0.43),
- MAIZE("MaizeMilletSorghum", "maize", true, false, 5.1, ModelConfig.INITAL_PRICE_MAIZE, 0.34),
- RICE("Rice (Paddy Equivalent)", "rice", true, false, 8.3, ModelConfig.INITAL_PRICE_RICE, 0.46),
- OILCROPS("Oilcrops", "oilcrops", true, false, 4.4, ModelConfig.INITAL_PRICE_OILCROPS, 0.24),
- PULSES("Pulses", "pulses", true, false, 10.8, ModelConfig.INITAL_PRICE_PULSES, 0.37),
- STARCHY_ROOTS("Starchy Roots", "starchyRoots", true, false, 14.3, ModelConfig.INITAL_PRICE_STARCHYROOTS, 0.13),
+ WHEAT("WheatBarleyOats", "wheat", true, false, 9.5, ModelConfig.INITAL_PRICE_WHEAT, 0.35),
+ MAIZE("MaizeMilletSorghum", "maize", true, false, 5.1, ModelConfig.INITAL_PRICE_MAIZE, 0.35),
+ RICE("Rice (Paddy Equivalent)", "rice", true, false, 8.3, ModelConfig.INITAL_PRICE_RICE, 0.35),
+ OILCROPS("Oilcrops", "oilcrops", true, false, 4.4, ModelConfig.INITAL_PRICE_OILCROPS, 0.25),
+ PULSES("Pulses", "pulses", true, false, 10.8, ModelConfig.INITAL_PRICE_PULSES, 0.35),
+ STARCHY_ROOTS("Starchy Roots", "starchyRoots", true, false, 14.3, ModelConfig.INITAL_PRICE_STARCHYROOTS, 0.15),
ENERGY_CROPS("Energy crops", "energycrops", true, false, 5, ModelConfig.INITAL_PRICE_ENERGYCROPS, 0.2),
SETASIDE("setaside", "setaside", false, false, 0, 0, 0),
- MONOGASTRICS("Monogastrics", "monogastrics", true, true, 3.1, ModelConfig.INITAL_PRICE_MONOGASTRICS, 0.20),
- RUMINANTS("Ruminants", "ruminants", true, true, 2.2, ModelConfig.INITAL_PRICE_RUMINANTS, 0.062),
- FRUITVEG("FruitVeg", "fruitveg", true, false, 8.9, ModelConfig.INITAL_PRICE_FRUITVEG, 0.032),
- SUGAR("Sugar", "sugar", true, false, 0.1, ModelConfig.INITAL_PRICE_SUGAR, 0.41),
+ MONOGASTRICS("Monogastrics", "monogastrics", true, true, 3.1, ModelConfig.INITAL_PRICE_MONOGASTRICS, 0.1),
+ RUMINANTS("Ruminants", "ruminants", true, true, 2.2, ModelConfig.INITAL_PRICE_RUMINANTS, 0.1),
+ FRUITVEG("FruitVeg", "fruitveg", true, false, 8.9, ModelConfig.INITAL_PRICE_FRUITVEG, 0.1),
+ SUGAR("Sugar", "sugar", true, false, 0.1, ModelConfig.INITAL_PRICE_SUGAR, 0.4),
PASTURE("pasture", "pasture", false, false, 0, 0, 0); // confusing having a land cover and a crop type. Needed here for yields (but not used for cropland area fractions).
private String faoName;
--
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