ŷ Y-Hat Symbol

Y-hat (ŷ) is the predicted value in regression — what your model says y should be, as opposed to the y you actually observed.

Also known as: y hat, y hat symbol, predicted value symbol, regression prediction symbol.

Codes

Windows0177, Alt + X

In Word, type 0177 then press Alt + X. Elsewhere, copy ŷ above or use Character Map (search “y with circumflex”).

Mac⌥ + I, then Y

Press Option + i (the circumflex dead key), then y. This one actually works — unlike p̂, because ŷ is a real precomposed character.

Microsoft Word0177, Alt + X

Type 0177, then press Alt + X. (Equation editor: type \hat y and press space.)

Google Docs

Insert → Special characters, then search “y with circumflex”. In an equation, \hat y followed by a space also works.

LaTeX\hat{y}

Use \hat{y} in math mode. \widehat{y} draws a wider hat.

ŷ is the fitted or predicted value: in simple linear regression, ŷ = b₀ + b₁x. The gap between the observed y and the predicted ŷ is the residual, y − ŷ.
The hat means estimate throughout statistics — ŷ estimates y, p̂ estimates p, and β̂ estimates β. Plain y is what you measured; ŷ is what the model claims.
★ Unlike p̂ and x̄, ŷ has a precomposed character. ŷ is U+0177 — a single code point — because it is a letter in Welsh, so Unicode encoded it as one. There is no precomposed “p with circumflex”, so p̂ is always two code points (p + U+0302). Same-looking notation, completely different encoding.
You can also write ŷ as y + U+0302 (two code points). The two forms are canonically equivalent: NFC composes them into U+0177 and NFD splits them apart, so either will survive normalization. That safety net does not exist for p̂ — nothing to compose to.