def phi_corr(x: list[int], y: list[int]) -> float: """ Calculate the Phi coefficient between two binary variables. Args: x (list[int]): A list of binary values (0 or 1). y (list[int]): A list of binary values (0 or 1). Returns: float: The Phi coefficient rounded to 4 decimal places. """ if len(x) != len(y): raise ValueError('Input lists must have the same length') a = b = c = d = 0 for x1, yi in zip(x, y): if x1 == 1 and yi == 1: a += 1 elif x1 == 1 and yi == 0: b += 1 elif x1 == 0 and yi == 1: c += 1 elif x1 == 0 and yi == 0: d += 1 else: raise ValueError('Inputs must be binary 0 or 1') numerator = a * d - b * c denominator = ((a + b)*(c + d)*(a + c)*(b + d)) ** 0.5 if denominator == 0: return 0.0 val = numerator / denominator return round(val,4) correct this