If you mean without using AVERAGEIF... you can use an AVERAGE array, commit using SHIFT + CTRL + ENTER

=AVERAGE(IF($A$2:$A$16=$A2,$B$2:$B$16))

Or you could combine a SUMIF & COUNTIF

=SUMIF($A$2:$A$16,$A2,$B$2:$B$16)/COUNTIF($A$2:$A$16,$A2)

(or use a Pivot Table)