"The orthogonality property of main effects and interactions present in balanced data does not carry over to the unbalanced case.
"ðɪ ˌɔːɹθəɡənˈælᵻɾi pɹˈɑːpɚɾi ʌv mˈeɪn ɪfˈɛkts ænd ˌɪntɚɹˈækʃənz pɹˈɛzənt ɪn bˈælənst dˈeɪɾə dʌznˌɑːt kˈæɹi ˌoʊvɚ tə ðɪ ʌnbˈælənst kˈeɪs.