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Time Series with PyTorch
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Convolution-based classification is similar to shapelets, in that they search for distinctive patterns, but they use a structure called a kernel which is a small, weighted pattern detector. As kernels/convolutions slide across a series a dot product is calculated for each step. Creating a new series, which we may refer to as a feature or activation map. For a time series
and a kernel
, the first value in the feature map is the dot product, like the 3-element kernel (often between 7-11 points):

From this feature map, we use ROCKET (Random Convolutional Kernel Transform) to extract: maximum value (max pooling) and proportion of positive values (PPV). The random part of ROCKET refers to randomization of kernel parameters: length, weights, bias, dilation, and padding.
For example, if a feature map has 10 values and 4 are positive, the PPV would be
.
These features generated by thousands (unlike shapelets) of random kernels create a transformed...