I have stumbled upon this character. How can I write it and would could it mean? It was used in order to describe forecasts. There, it said:
The forecast value for period $T + k$ (with $T = \text{end of the observation period}$ and $k = \text{number of observation points in the future}$) by point estimation is given by: $$\hat Y = a + b * t$$ $$\hat y_{T + k} = a + b * (T + k)$$
$\hat y$ represents the very character.
Edit: I have found the solution how to make such a character. But I still do not know what it could mean.
