Paper:

# Self-Structured Cortical Learning Algorithm by Dynamically Adjusting Columns and Cells

## Sotetsu Suzugamine, Takeru Aoki, Keiki Takadama, and Hiroyuki Sato

Graduate School of Information and Engineering Sciences, The University of Electro-Communications

1-5-1 Chofugaoka, Chofu, Tokyo 182-8585, Japan

The cortical learning algorithm (CLA) is a type of time-series data prediction algorithm based on the human neocortex. CLA uses multiple columns to represent an input data value at a timestep, and each column has multiple cells to represent the time-series context of the input data. In the conventional CLA, the numbers of columns and cells are user-defined parameters. These parameters depend on the input data, which can be unknown before learning. To avoid the necessity for setting these parameters beforehand, in this work, we propose a self-structured CLA that dynamically adjusts the numbers of columns and cells according to the input data. The experimental results using the time-series test inputs of a sine wave, combined sine wave, and logistic map data demonstrate that the proposed self-structured algorithm can dynamically adjust the numbers of columns and cells depending on the input data. Moreover, the prediction accuracy is higher than those of the conventional long short-term memory and CLAs with various fixed numbers of columns and cells. Furthermore, the experimental results on a multistep prediction of real-world power consumption show that the proposed self-structured CLA achieves a higher prediction accuracy than the conventional long short-term memory.

*J. Adv. Comput. Intell. Intell. Inform.*, Vol.24 No.2, pp. 185-198, 2020.

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