functime-org / functime

Time-series machine learning at scale. Built with Polars for embarrassingly parallel feature extraction and forecasts on panel data.
https://docs.functime.ai
Apache License 2.0
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Allow for models to make predictions at time t without using y_t #152

Open ngriffiths13 opened 6 months ago

ngriffiths13 commented 6 months ago

Is your feature request related to a problem? Please describe. I have a target variable that is the difference between x_t and x_t+500. This target variable is represented as y_t. I want to set up a model that looks like this:

skew*B_0 + imbalance*B_1 = y_t(price_t - price_t+500)

Describe the solution you'd like I want to support forecasters that can do 2 things:

  1. Make a prediction like a regular ML model would and works in our backtesting framework. (A time series prediction that is not exactly forecasting).
  2. Can use lagged y values from at least n timestamps ago (in this example n=500 because that is the most recent y we would have known at time t).

Describe alternatives you've considered You could do a bunch of lags and stuff. Definitely goes against user friendliness.

Additional context I am not sure if this is technically forecasting... But it is time series prediction and I feel like it is actually a better use case than forecasting. It will also allow us to set up time series classification and generally be more flexible. It should fit into the backtesting framework nicely.