public static ArrayList<ItemType> mockItems(
int numberOfItems, Collection<CategoryNode> categories) {
Random r = new Random();
ArrayList<ItemType> items = new ArrayList<>();
ExponentialDistribution exp1 = new ExponentialDistribution(1);
int averageValuation = 6195; // from TM data
int minimumValuation = 400;
ExponentialDistribution exp2 = new ExponentialDistribution(averageValuation);
for (int i = 0; i < numberOfItems; i++) {
double weight = exp1.sample();
int trueValuation;
do {
trueValuation = (int) (exp2.sample() + 0.5);
} while (trueValuation < minimumValuation);
ItemType item =
new ItemType(
weight,
"type" + (int) (weight * 10000),
trueValuation,
CategoryRecord.randomCategory(categories, r.nextDouble()));
items.add(item);
}
CreateItemTypes.normaliseWeights(items);
return items;
}
private void submitAuction() {
double logParam = 2.5; // from TM data. See countCategorySpread.xlsx
ItemType type;
if (useNewAuctionCategory(++auctionsSubmitted, logParam, r.nextDouble())) { // pick a new type
type = CreateItemTypes.pickType(itemTypes, r.nextDouble());
itemTypesUsed.add(type);
} else { // use an previously used type
type = chooseOldItemType(logParam, itemTypesUsed, r.nextDouble());
}
Item newItem = new Item(type, "item" + r.nextInt(100000));
double popularity;
if (r.nextDouble() < 0.5) popularity = 0.7;
else popularity = 1;
Auction auction = new Auction(this, newItem, 2016, 100, 0, popularity);
this.bh.getAuctionMessagesToAh().put(auction);
}
