The use of deep neural networks to make high risk decisions creates a need
for global and local explanations so that users and experts have confidence in
the modeling algorithms. We introduce a novel technique to find global and
local explanations for time series data used in binary classification machine
learning systems. We identify the most salient of the original features used by
a black box model to distinguish between classes. The explanation can be made
on categorical, continuous, and time series data and can be generalized to any
binary classification model. The analysis is conducted on time series data to
train a long short-term memory deep neural network and uses the time dependent
structure of the underlying features in the explanation. The proposed technique
attributes weights to features to explain an observations risk of belonging to
a class as a multiplicative factor of a base hazard rate. We use a variation of
the Cox Proportional Hazards regression, a Generalized Additive Model, to
explain the effect of variables upon the probability of an in-class response
for a score output from the black box model. The covariates incorporate time
dependence structure in the features so the explanation is inclusive of the
underlying time series data structure.

使用深度神经网络进行高风险决策需要全局和局部解释，我们提出了一种用于发现二元分类机器学习系统中使用的时间序列数据的全局和局部解释的新技术，使用 Cox 比例风险回归的变体对变量的影响进行解释。