from typing import List


def cal_information_gains(prior_entropies, pred_entropies) -> List[float]:
    """
    Calculate information gains from prior and prediction entropies

    :param prior_entropies: prior entropies
    :param pred_entropies: prediction entropies
    :return: list of information gain for each entry
    """
    info_gains = list()
    for i in range(len(pred_entropies)):
        info_gain = prior_entropies[i] - pred_entropies[i]
        info_gains.append(info_gain)

    return info_gains