adding the full code base and changing the numbering of chapters

Chapter 3 - Offices and Restrooms/ex-3.13.r

@@ -0,0 +1,10 @@
+data <- read.table("simulation3-4.csv", header=TRUE, sep=",")
+df <- data.frame(table(data$X400))
+colnames(df) <- c("queue_size", "frequency")
+percent_labels <- paste(df$frequency, '\n', round(df$frequency*100/540, 2), '%')
+
+ggplot(data=df) + opts(legend.position = "none") + 
+  geom_bar(aes(x = queue_size, y = frequency, fill = factor(queue_size))) +
+  geom_text(aes(x = queue_size, y = frequency, label = percent_labels, size=1)) +
+  scale_y_continuous("frequency") +
+  scale_x_discrete("queue size")

Chapter 4 - Offices and restrooms/exp5_2.r → Chapter 3 - Offices and Restrooms/exp5_2.r

@@ -5,7 +5,7 @@ pdf("ch04_ex5_2.pdf")
 data <- read.table("simulation3.csv", header=TRUE, sep=",")
 df <- data.frame(table(data$X400))
 colnames(df) <- c("queue_size", "frequency")
-percent_labels <- paste(df$frequency, '(', round(df$frequency*100/540, 2), '%)')
+percent_labels <- paste(df$frequency, '\n', round(df$frequency*100/540, 2), '%')
 
 ggplot(data=df) + opts(legend.position = "none") + 
   geom_bar(aes(x = queue_size, y = frequency, fill = factor(queue_size))) +

Chapter 4 - How to Be an Armchair Economist/s1_demand_supply.r

@@ -0,0 +1,10 @@
+library(ggplot2)
+data <- read.table("demand_supply.csv", header=F, sep=",")
+
+pdf("demand_supply.pdf")
+ggplot(data = data) + scale_colour_grey(name="Legend", start=0, end=0.6) +
+  geom_line(aes(x  = V1, y = V2, color = "demand")) +
+  geom_line(aes(x  = V1, y = V3, color = "supply")) +
+  scale_y_continuous("amount") +
+  scale_x_continuous("time")
+dev.off()

Chapter 4 - How to Be an Armchair Economist/s1_price_demand.r

@@ -0,0 +1,10 @@
+library(ggplot2)
+data <- read.table("price_demand.csv", header=F, sep=",")
+
+pdf("price_demand.pdf")
+ggplot(data = data) + scale_colour_grey(name="Legend", start=0, end=0.6) +
+  geom_line(aes(x  = V1, y = V2, color = "price")) +
+  geom_line(aes(x  = V1, y = log2(V3)-3, color = "demand")) +
+    scale_y_continuous("amount") +
+    scale_x_continuous("time")
+dev.off()

Chapter 4 - How to Be an Armchair Economist/s2_price_compare.r

@@ -0,0 +1,10 @@
+library(ggplot2)
+data <- read.table("price_data.csv", header=F, sep=",")
+
+pdf("price_compare.pdf")
+ggplot(data = data) + scale_colour_grey(name="Average price", start=0, end=0.6) +
+  geom_line(aes(x  = V1, y = V2, color = "chickens")) +
+  geom_line(aes(x  = V1, y = V3, color = "ducks")) +
+  scale_y_continuous("price") +  
+  scale_x_continuous("time")
+dev.off()

Chapter 4 - How to Be an Armchair Economist/s2_supply_compare.r

@@ -0,0 +1,10 @@
+library(ggplot2)
+data <- read.table("supply_data.csv", header=F, sep=",")
+
+pdf("supply_compare.pdf")
+ggplot(data = data) + scale_colour_grey(name="Supply", start=0, end=0.6) +
+  geom_line(aes(x  = V1, y = V2, color = "chickens")) +
+  geom_line(aes(x  = V1, y = V3, color = "ducks")) +
+  scale_y_continuous("amount") +  
+  scale_x_continuous("time")
+dev.off()

Chapter 4 - How to Be an Armchair Economist/simulation1.rb

@@ -0,0 +1,127 @@
+require 'csv'
+
+SIMULATION_DURATION = 150
+NUM_OF_PRODUCERS = 10
+NUM_OF_CONSUMERS = 10
+
+MAX_STARTING_SUPPLY = 20
+SUPPLY_INCREMENT = 80
+
+COST = 5
+MAX_ACCEPTABLE_PRICE = COST * 10
+MAX_STARTING_PROFIT = 5
+PRICE_INCREMENT = 1.1
+PRICE_DECREMENT = 0.9
+
+
+class Producer
+  attr_accessor :supply, :price
+  def initialize
+    @supply, @price = 0, 0
+  end
+
+  def generate_goods
+   @supply += SUPPLY_INCREMENT if @price > COST
+  end
+
+  def produce
+    if @supply > 0
+      @price *= PRICE_DECREMENT unless @price < COST
+    else
+      @price *= PRICE_INCREMENT
+      generate_goods
+    end
+  end
+end
+
+class Consumer
+  attr_accessor :demands
+
+  def initialize
+    @demands = 0
+  end
+
+  def buy    
+    until @demands <= 0 or Market.supply <= 0 
+      cheapest_producer = Market.cheapest_producer
+      if cheapest_producer
+        @demands *= 0.5 if cheapest_producer.price > MAX_ACCEPTABLE_PRICE
+        cheapest_supply = cheapest_producer.supply
+        if @demands > cheapest_supply
+          @demands -= cheapest_supply
+          cheapest_producer.supply = 0
+        else        
+          cheapest_producer.supply -= @demands
+          @demands = 0
+        end
+      end
+    end
+  end
+end
+
+class Market
+  def self.average_price
+    ($producers.inject(0.0) { |memo, producer| memo + producer.price}/$producers.size).round(2)
+  end  
+
+  def self.supply
+    $producers.inject(0) { |memo, producer| memo + producer.supply }
+  end
+
+  def self.demand
+    $consumers.inject(0) { |memo, consumer| memo + consumer.demands }
+  end
+
+  def self.cheapest_producer
+    producers = $producers.find_all {|f| f.supply > 0} 
+    producers.min_by{|f| f.price}
+  end
+end
+
+def write(name,data)
+  CSV.open("#{name}.csv", 'w') do |csv|
+    data.each do |row|
+      csv << row
+    end
+  end  
+end
+
+$producers = []
+NUM_OF_PRODUCERS.times do
+  producer = Producer.new
+  producer.price = COST + rand(MAX_STARTING_PROFIT)
+  producer.supply = rand(MAX_STARTING_SUPPLY)
+  $producers << producer
+end
+
+$consumers = []
+NUM_OF_CONSUMERS.times do
+  $consumers << Consumer.new
+end
+
+$generated_demand  = []
+SIMULATION_DURATION.times {|n| $generated_demand << ((Math.sin(n)+2)*20).round  }
+
+demand_supply, price_demand = [], []
+
+SIMULATION_DURATION.times do |t|
+  $consumers.each do |consumer|
+    consumer.demands = $generated_demand[t]
+  end
+  demand_supply << [t, Market.demand, Market.supply]
+
+  $producers.each do |producer|
+    producer.produce
+  end
+
+  price_demand << [t, Market.average_price, Market.demand]
+
+  until Market.demand == 0 or Market.supply == 0 do
+    $consumers.each do |consumer|
+      consumer.buy 
+    end
+  end
+end
+
+write("demand_supply", demand_supply)
+write("price_demand", price_demand)

Chapter 4 - How to Be an Armchair Economist/simulation2.rb

@@ -0,0 +1,149 @@
+require 'csv'
+
+SIMULATION_DURATION = 150
+NUM_OF_PRODUCERS = 10
+NUM_OF_CONSUMERS = 10
+
+MAX_STARTING_SUPPLY = Hash.new
+MAX_STARTING_SUPPLY[:ducks] = 20
+MAX_STARTING_SUPPLY[:chickens] = 20
+SUPPLY_INCREMENT = 60
+
+COST = Hash.new
+COST[:ducks] = 23
+COST[:chickens] = 12
+
+MAX_ACCEPTABLE_PRICE = Hash.new
+MAX_ACCEPTABLE_PRICE[:ducks] = COST[:ducks] * 10
+MAX_ACCEPTABLE_PRICE[:chickens] = COST[:chickens] * 10
+
+MAX_STARTING_PROFIT = Hash.new
+MAX_STARTING_PROFIT[:ducks] = 15
+MAX_STARTING_PROFIT[:chickens] = 15
+PRICE_INCREMENT = 1.1
+PRICE_DECREMENT = 0.9
+
+class Producer
+  attr_accessor :supply, :price
+  def initialize
+    @supply, @supply[:chickens], @supply[:ducks] = {}, 0, 0
+    @price, @price[:chickens], @price[:ducks] = {}, 0, 0
+  end
+
+  def change_pricing
+    @price.each do |type, price|
+      if @supply[type] > 0
+        @price[type] *= PRICE_DECREMENT unless @price[type] < COST[type]
+      else
+        @price[type] *= PRICE_INCREMENT
+      end
+    end
+  end
+
+  def generate_goods
+    to_produce = Market.average_price(:chickens) > Market.average_price(:ducks) ? :chickens : :ducks
+    @supply[to_produce] += (SUPPLY_INCREMENT) if @price[to_produce] > COST[to_produce]
+  end
+
+  def produce
+    change_pricing
+    generate_goods
+  end
+end
+
+class Consumer
+  attr_accessor :demands
+
+  def initialize
+    @demands = 0
+  end
+
+  def buy(type)
+    until @demands <= 0 or Market.supply(type) <= 0
+      cheapest_producer = Market.cheapest_producer(type)
+      if cheapest_producer
+        @demands *= 0.5 if cheapest_producer.price[type] > MAX_ACCEPTABLE_PRICE[type]
+        cheapest_supply = cheapest_producer.supply[type]
+        if @demands > cheapest_supply then
+          @demands -= cheapest_supply
+          cheapest_producer.supply[type] = 0
+        else        
+          cheapest_producer.supply[type] -= @demands
+          @demands = 0
+        end
+      end
+    end
+  end
+end
+
+class Market
+  def self.average_price(type)
+    ($producers.inject(0.0) { |memo, producer| memo + producer.price[type]}/$producers.size).round(2)
+  end  
+
+  def self.supply(type)
+    $producers.inject(0) { |memo, producer| memo + producer.supply[type] }
+  end
+
+  def self.demands
+    $consumers.inject(0) { |memo, consumer| memo + consumer.demands }
+  end
+
+  def self.cheaper(a,b)
+    cheapest_a_price = $producers.min_by {|f| f.price[a]}.price[a]
+    cheapest_b_price = $producers.min_by {|f| f.price[b]}.price[b]
+    cheapest_a_price < cheapest_b_price ? a : b
+  end 
+
+  def self.cheapest_producer(type)
+    producers = $producers.find_all {|producer| producer.supply[type] > 0} 
+    producers.min_by{|producer| producer.price[type]}
+  end
+end
+
+def write(name,data)
+  CSV.open("#{name}.csv", 'w') do |csv|
+    data.each do |row|
+      csv << row
+    end
+  end  
+end
+
+$producers = []
+NUM_OF_PRODUCERS.times do
+  producer = Producer.new
+  producer.price[:chickens] = COST[:chickens] + rand(MAX_STARTING_PROFIT[:chickens])
+  producer.price[:ducks]    = COST[:ducks] + rand(MAX_STARTING_PROFIT[:ducks])
+  producer.supply[:chickens] = rand(MAX_STARTING_SUPPLY[:chickens])
+  producer.supply[:ducks]    = rand(MAX_STARTING_SUPPLY[:ducks])
+  $producers << producer
+end
+
+$consumers = []
+NUM_OF_CONSUMERS.times do
+  $consumers << Consumer.new
+end
+
+$generated_demand  = []
+SIMULATION_DURATION.times {|n| $generated_demand << ((Math.sin(n)+2)*20).round }
+
+price_data, supply_data = [], []
+SIMULATION_DURATION.times do |t|
+  $consumers.each do |consumer|
+    consumer.demands = $generated_demand[t]
+  end
+  supply_data << [t, Market.supply(:chickens), Market.supply(:ducks)]
+  $producers.each do |producer|
+    producer.produce    
+  end
+  cheaper_type = Market.cheaper(:chickens, :ducks)
+  until Market.demands == 0 or Market.supply(cheaper_type) == 0  do
+    $consumers.each do |consumer|
+      consumer.buy cheaper_type
+    end
+  end
+  price_data << [t, Market.average_price(:chickens), Market.average_price(:ducks)]
+end
+
+write("price_data", price_data)
+write("supply_data", supply_data)