Secondly, in this situation, 0° (or 360°) is geometrically a better average value: there is lower dispersion about it (the points are both 1° from it and 179° from 180°, the putative average).
sˈɛkəndli, ɪn ðɪs sˌɪtʃuːˈeɪʃən, zˈiəɹoʊ dᵻɡɹˈiːz ɔːɹ θɹˈiːhˈʌndɹɪd sˈɪksti dᵻɡɹˈiːz ɪz dʒˌiːoʊmˈɛtɹɪkli ɐ bˈɛɾɚɹ ˈævɹɪdʒ vˈæljuː: ðɛɹ ɪz lˈoʊɚ dɪspˈɜːʒən ɐbˌaʊt ɪt ðə pˈɔɪnts ɑːɹ bˈoʊθ wˈʌn dᵻɡɹˈiːz fɹʌm ɪt ænd wˈʌnhˈʌndɹɪd sˈɛvənti nˈaɪn dᵻɡɹˈiːz fɹʌm wˈʌnhˈʌndɹɪd ˈeɪɾi dᵻɡɹˈiːz, ðə pjˈuːɾətˌɪv ˈævɹɪdʒ.