Informer
What is informer ?
Informer is a time series model which is a part of the Transformer family.
It’s a transformer based model designed for Long sequence time-series forecasting (LSTF). Informer has shown a remarkable ability to capture both long-term patterns and short-term fluctuations.
Informer architechture
Advantage over transformers
Informer solves two major problems of a transformer
1.Quadratic Time Complexity of Attention Mechanism
By using probSparse attention, informer reduces the time complexity of the attention mechanism from quadratic to O(n logn). Instead of each token attending to every other token, they restrict attention to a limited number of relevant tokens,
2.Memory Bottleneck of stacking layers for long inputs
Distillation is a technique which chooses only the active queries from the probSparse and reduces the space required by the subsequent layer. Thus it can further enhance memory efficiency.