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With the further liberalization of the electricity market of China, customers’ requirements, characteristics, and distribution, as well as the quality, security, and reliability of power supplies without interruption, have received considerable attention from power companies, policymakers, and researchers. How to deeply explore the distribution characteristics of electricity customers and analyze their sensitivities to electricity blackouts has become an especially important problem. This paper takes over 0.1 billion data, collected by various smart devices of the Internet of Things in the power system of China, such as smart meters, intelligent power consumption interactive terminals, data concentrators, and other cross-platform data, for example, 95 598 telephone records, complaint information, user bills, user information, and maintenance records, as study objects, to analyze the consumption characteristics of power users. It has been found that there is a wide range of power users who pay different electricity bills; a long-tail distribution following a power law lies in the number of users versus their paid electricity bills. Meanwhile, there are two Pareto effects (2-8 rule): the number of residents and non-residents versus their electricity bills, and the number of large industrial users and general industry (business users) versus in their electricity consumption and bills. Then, a decision tree algorithm is proposed to capture the characteristics of electricity consumers and to recognize the crowd who is power blackout sensitive. The evaluation indexes and parameters of the decision tree are discussed in detail, and a comparison with other intelligent algorithms shows that the decision tree has a good recognition performance over that of others, and the characteristics used to identify the blackout-sensitive crowd is various. All the results state that except for economic factors, positive social effects should also be considered. Various marketing strategies to satisfy different requirements of power users should be provided to promote long-term relationships between the power companies and power customers.

Regardless of the type of data, traditional Bloom filters treat each element of a set as a string, and by iterating every character of the string, they discretize all data randomly and uniformly. However, with the data size and dimension increases, these variants are inefficient. To better discretize vectors with high numerical dimensions, this paper improves the string hashes to integer hashes. Based on the integer hashes and a counter array, we propose a new variant—high-dimensional bloom filter (HDBF)—to extend the Bloom filter into high-dimensional spaces, which can represent and query numerical vectors of a big set with a low false positive probability. This paper theoretically analyzes the feasibility of the integer hashes on discretizing data and discusses the relationship of parameters of the HDBF. The experiments illustrate that, in high-dimensional numerical spaces, the HDBF shows better randomness on distribution and entropy than that of the counting Bloom filter. Compared with the parallel Bloom filters, for a fixed false positive probability, the HDBF displays time-space overheads, and is more suitable to deal with the numerical vectors with high dimensions.