`importance_weights()`

creates a vector of importance weights which allow you
to apply a context dependent weight to your observations. Importance weights
are supplied as a non-negative double vector, where fractional values are
allowed.

## Examples

```
importance_weights(c(1.5, 2.3, 10))
#> <importance_weights[3]>
#> [1] 1.5 2.3 10.0
```