pairwise_losses.py 文件源码

def logistic_loss(positive_scores, negative_scores):
    """
    Pairwise logistic loss [1]:
        loss(p, n) = \sum_i log(1 + e^(1 - p_i + n_i))

    [1] http://yann.lecun.com/exdb/publis/pdf/lecun-06.pdf

    Args:
        positive_scores: (N,) Tensor containing scores of positive examples.
        negative_scores: (N,) Tensor containing scores of negative examples.
    Returns:
        Loss value.
    """
    logistic_losses = tf.log(1 + tf.exp(1 - positive_scores + negative_scores))
    loss = tf.reduce_sum(logistic_losses)
    return loss