diff --git a/pams/market.py b/pams/market.py
index b779c340..323b865a 100644
--- a/pams/market.py
+++ b/pams/market.py
@@ -806,11 +806,11 @@ def remain_executable_orders(self) -> bool:
                 if sell_book[None] < buy_book[None]:
                     additional_required_orders = buy_book[None] - sell_book[None]
                     sell_book.pop(None)
-                    return len(sell_book) > additional_required_orders
+                    return len(sell_book) >= additional_required_orders
                 else:
                     additional_required_orders = sell_book[None] - buy_book[None]
                     buy_book.pop(None)
-                    return len(buy_book) > additional_required_orders
+                    return len(buy_book) >= additional_required_orders
             else:
                 sell_book.pop(None)
                 buy_book.pop(None)
diff --git a/pams/version.py b/pams/version.py
index 6561790f..d62d9673 100644
--- a/pams/version.py
+++ b/pams/version.py
@@ -1 +1 @@
-__version__ = "0.0.15"
+__version__ = "0.0.16"
diff --git a/pyproject.toml b/pyproject.toml
index 1211bc1c..68e99056 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "pams"
-version = "0.0.15"
+version = "0.0.16"
 description = "PAMS: Platform for Artificial Market Simulations"
 authors = ["Masanori HIRANO <masa.hirano.1996@gmail.com>"]
 license = "MIT"
diff --git a/tests/pams/test_market.py b/tests/pams/test_market.py
index 4a7768e8..83e35ba3 100644
--- a/tests/pams/test_market.py
+++ b/tests/pams/test_market.py
@@ -127,7 +127,7 @@ def test_init__(self) -> None:
         assert m.get_n_sell_orders() == [0, 1, 0]
         assert m.get_n_sell_order() == 0
         assert m.get_mid_prices() == [None, None, None]
-        assert m.get_mid_price() == None
+        assert m.get_mid_price() is None
         assert m.get_vwap() == 1.0
         order3 = Order(
             agent_id=0, market_id=0, is_buy=False, kind=LIMIT_ORDER, volume=1, price=1.2
@@ -463,11 +463,14 @@ def test_execution(self) -> None:
         if len(logs) == 0:
             raise AssertionError
         start_time = time.time()
+        n_logs = 0
+        total_volume = 0
         for _ in range(5000):
-            kind = LIMIT_ORDER if random.random() < 0.7 else MARKET_ORDER
+            kind = LIMIT_ORDER if random.random() < 0.6 else MARKET_ORDER
             price = random.random() * 10 if kind == LIMIT_ORDER else None
             ttl = random.randint(1, 100) if bool(random.getrandbits(1)) else None
             volume = random.randint(1, 10)
+            total_volume += volume
             order = Order(
                 agent_id=0,
                 market_id=0,
@@ -479,9 +482,270 @@ def test_execution(self) -> None:
             )
             market._add_order(order)
             log = market._execution()
-            assert len(log) <= volume
+            n_logs += len(log)
             market._update_time(1.0)
+        assert n_logs <= total_volume
         end_time = time.time()
         time_per_step = (end_time - start_time) / 10000
         print("time/step", time_per_step)
         assert time_per_step < 0.005
+
+    def test_execution_order_pattern1(self) -> None:
+        market = self.base_class(
+            market_id=0,
+            prng=random.Random(42),
+            logger=Logger(),
+            simulator=Simulator(prng=random.Random(42)),
+            name="test",
+        )
+        market._update_time(1.0)
+        market._is_running = True
+        order = Order(
+            agent_id=0, market_id=0, is_buy=True, kind=LIMIT_ORDER, volume=1, price=10
+        )
+        market._add_order(order)
+        assert not market.remain_executable_orders()
+        logs = market._execution()
+        assert len(logs) == 0
+
+    def test_execution_order_pattern2(self) -> None:
+        market = self.base_class(
+            market_id=0,
+            prng=random.Random(42),
+            logger=Logger(),
+            simulator=Simulator(prng=random.Random(42)),
+            name="test",
+        )
+        market._update_time(1.0)
+        market._is_running = True
+        order = Order(
+            agent_id=0, market_id=0, is_buy=False, kind=LIMIT_ORDER, volume=1, price=10
+        )
+        market._add_order(order)
+        assert not market.remain_executable_orders()
+        logs = market._execution()
+        assert len(logs) == 0
+
+    def test_execution_order_pattern3(self) -> None:
+        market = self.base_class(
+            market_id=0,
+            prng=random.Random(42),
+            logger=Logger(),
+            simulator=Simulator(prng=random.Random(42)),
+            name="test",
+        )
+        market._update_time(1.0)
+        market._is_running = True
+        order = Order(
+            agent_id=0, market_id=0, is_buy=False, kind=MARKET_ORDER, volume=1
+        )
+        market._add_order(order)
+        order = Order(agent_id=0, market_id=0, is_buy=True, kind=MARKET_ORDER, volume=1)
+        market._add_order(order)
+        assert not market.remain_executable_orders()
+        logs = market._execution()
+        assert len(logs) == 0
+
+    def test_execution_order_pattern4(self) -> None:
+        market = self.base_class(
+            market_id=0,
+            prng=random.Random(42),
+            logger=Logger(),
+            simulator=Simulator(prng=random.Random(42)),
+            name="test",
+        )
+        market._update_time(1.0)
+        market._is_running = True
+        order = Order(
+            agent_id=0, market_id=0, is_buy=False, kind=MARKET_ORDER, volume=1
+        )
+        market._add_order(order)
+        order = Order(agent_id=0, market_id=0, is_buy=True, kind=MARKET_ORDER, volume=1)
+        market._add_order(order)
+        order = Order(
+            agent_id=0, market_id=0, is_buy=True, kind=LIMIT_ORDER, volume=1, price=10
+        )
+        market._add_order(order)
+        order = Order(
+            agent_id=0, market_id=0, is_buy=False, kind=LIMIT_ORDER, volume=1, price=9
+        )
+        market._add_order(order)
+        assert market.remain_executable_orders()
+        logs = market._execution()
+        assert len(logs) == 2
+
+    def test_execution_order_pattern5(self) -> None:
+        market = self.base_class(
+            market_id=0,
+            prng=random.Random(42),
+            logger=Logger(),
+            simulator=Simulator(prng=random.Random(42)),
+            name="test",
+        )
+        market._update_time(1.0)
+        market._is_running = True
+        order = Order(
+            agent_id=0, market_id=0, is_buy=False, kind=LIMIT_ORDER, volume=2, price=8
+        )
+        market._add_order(order)
+        order = Order(
+            agent_id=0, market_id=0, is_buy=True, kind=LIMIT_ORDER, volume=1, price=9
+        )
+        market._add_order(order)
+        order = Order(
+            agent_id=0, market_id=0, is_buy=True, kind=LIMIT_ORDER, volume=1, price=10
+        )
+        market._add_order(order)
+        order = Order(
+            agent_id=0, market_id=0, is_buy=False, kind=LIMIT_ORDER, volume=1, price=9
+        )
+        market._add_order(order)
+        assert market.remain_executable_orders()
+        logs = market._execution()
+        assert len(logs) == 2
+
+    def test_execution_order_pattern6(self) -> None:
+        market = self.base_class(
+            market_id=0,
+            prng=random.Random(42),
+            logger=Logger(),
+            simulator=Simulator(prng=random.Random(42)),
+            name="test",
+        )
+        market._update_time(1.0)
+        market._is_running = True
+        order = Order(
+            agent_id=0, market_id=0, is_buy=False, kind=LIMIT_ORDER, volume=1, price=8
+        )
+        market._add_order(order)
+        order = Order(
+            agent_id=0, market_id=0, is_buy=True, kind=LIMIT_ORDER, volume=2, price=11
+        )
+        market._add_order(order)
+        order = Order(
+            agent_id=0, market_id=0, is_buy=True, kind=LIMIT_ORDER, volume=1, price=10
+        )
+        market._add_order(order)
+        order = Order(
+            agent_id=0, market_id=0, is_buy=False, kind=LIMIT_ORDER, volume=1, price=9
+        )
+        market._add_order(order)
+        assert market.remain_executable_orders()
+        logs = market._execution()
+        assert len(logs) == 2
+
+    def test_execution_order_pattern7(self) -> None:
+        market = self.base_class(
+            market_id=0,
+            prng=random.Random(42),
+            logger=Logger(),
+            simulator=Simulator(prng=random.Random(42)),
+            name="test",
+        )
+        market._update_time(1.0)
+        market._is_running = True
+        order = Order(
+            agent_id=0, market_id=0, is_buy=False, kind=LIMIT_ORDER, volume=1, price=8
+        )
+        market._add_order(order)
+        order = Order(
+            agent_id=0, market_id=0, is_buy=True, kind=LIMIT_ORDER, volume=1, price=11
+        )
+        market._add_order(order)
+        order = Order(
+            agent_id=0, market_id=0, is_buy=True, kind=LIMIT_ORDER, volume=1, price=9
+        )
+        market._add_order(order)
+        order = Order(
+            agent_id=0, market_id=0, is_buy=False, kind=LIMIT_ORDER, volume=1, price=10
+        )
+        market._add_order(order)
+        assert market.remain_executable_orders()
+        logs = market._execution()
+        assert len(logs) == 1
+
+    def test_execution_order_pattern8(self) -> None:
+        market = self.base_class(
+            market_id=0,
+            prng=random.Random(42),
+            logger=Logger(),
+            simulator=Simulator(prng=random.Random(42)),
+            name="test",
+        )
+        market._update_time(1.0)
+        market._is_running = True
+        order = Order(
+            agent_id=0, market_id=0, is_buy=False, kind=MARKET_ORDER, volume=1
+        )
+        market._add_order(order)
+        order = Order(
+            agent_id=0, market_id=0, is_buy=True, kind=LIMIT_ORDER, volume=1, price=11
+        )
+        market._add_order(order)
+        order = Order(
+            agent_id=0, market_id=0, is_buy=True, kind=LIMIT_ORDER, volume=1, price=9
+        )
+        market._add_order(order)
+        order = Order(
+            agent_id=0, market_id=0, is_buy=False, kind=LIMIT_ORDER, volume=1, price=10
+        )
+        market._add_order(order)
+        assert market.remain_executable_orders()
+        logs = market._execution()
+        assert len(logs) == 1
+
+    def test_execution_order_pattern9(self) -> None:
+        market = self.base_class(
+            market_id=0,
+            prng=random.Random(42),
+            logger=Logger(),
+            simulator=Simulator(prng=random.Random(42)),
+            name="test",
+        )
+        market._update_time(1.0)
+        market._is_running = True
+        order = Order(
+            agent_id=0, market_id=0, is_buy=False, kind=LIMIT_ORDER, volume=1, price=8
+        )
+        market._add_order(order)
+        order = Order(agent_id=0, market_id=0, is_buy=True, kind=MARKET_ORDER, volume=1)
+        market._add_order(order)
+        order = Order(
+            agent_id=0, market_id=0, is_buy=True, kind=LIMIT_ORDER, volume=1, price=9
+        )
+        market._add_order(order)
+        order = Order(
+            agent_id=0, market_id=0, is_buy=False, kind=LIMIT_ORDER, volume=1, price=10
+        )
+        market._add_order(order)
+        assert market.remain_executable_orders()
+        logs = market._execution()
+        assert len(logs) == 1
+
+    def test_execution_order_pattern10(self) -> None:
+        market = self.base_class(
+            market_id=0,
+            prng=random.Random(42),
+            logger=Logger(),
+            simulator=Simulator(prng=random.Random(42)),
+            name="test",
+        )
+        market._update_time(1.0)
+        market._is_running = True
+        order = Order(
+            agent_id=0, market_id=0, is_buy=False, kind=MARKET_ORDER, volume=2
+        )
+        market._add_order(order)
+        order = Order(agent_id=0, market_id=0, is_buy=True, kind=MARKET_ORDER, volume=1)
+        market._add_order(order)
+        order = Order(
+            agent_id=0, market_id=0, is_buy=True, kind=LIMIT_ORDER, volume=1, price=9
+        )
+        market._add_order(order)
+        order = Order(
+            agent_id=0, market_id=0, is_buy=False, kind=LIMIT_ORDER, volume=1, price=10
+        )
+        market._add_order(order)
+        assert market.remain_executable_orders()
+        logs = market._execution()
+        assert len(logs) == 2