diff --git a/pyswarms/discrete/binary.py b/pyswarms/discrete/binary.py
index 7ae5bc8b..ed20b8f3 100644
--- a/pyswarms/discrete/binary.py
+++ b/pyswarms/discrete/binary.py
@@ -14,7 +14,7 @@
 
 .. math::
 
-   v_{ij}(t + 1) = m * v_{ij}(t) + c_{1}r_{1j}(t)[y_{ij}(t) − x_{ij}(t)] + c_{2}r_{2j}(t)[\hat{y}_{j}(t) − x_{ij}(t)]
+   v_{ij}(t + 1) = w * v_{ij}(t) + c_{1}r_{1j}(t)[y_{ij}(t) − x_{ij}(t)] + c_{2}r_{2j}(t)[\hat{y}_{j}(t) − x_{ij}(t)]
 
 For the velocity update rule, a particle compares its current position
 with respect to its neighbours. The nearest neighbours are being
@@ -87,7 +87,7 @@ def __init__(
             number of particles in the swarm.
         dimensions : int
             number of dimensions in the space.
-        options : dict with keys :code:`{'c1', 'c2', 'k', 'p'}`
+        options : dict with keys :code:`{'c1', 'c2', 'w', 'k', 'p'}`
             a dictionary containing the parameters for the specific
             optimization technique
                 * c1 : float