RELATIVE PREDICTIVE POWER OF THE OPTIMISM VERSUS THE PESSIMISM INDEX OF A CHINESE VERSION OF THE LIFE ORIENTATION TEST

To examine the dimensionality of the Life Orientation Test (LOT) (a me asure of optimism) in Hong Kong Chinese, a Chinese version of the LOT, a physical symptoms checklist, and the Chinese Affect Scale were admi nistered to two separate samples of 230 undergraduates and 173 working adults. Exploratory factor analysis showed that the LOT was split bet ween the optimism and the pessimism indices in both samples, but these two factors were not correlated differentially with either symptom re ports or affective measures. On balance, the two indices do differ in one important aspect. The predictive power of the complete LOT was con ferred mainly by the optimism rather than the pessimism index. These f indings indicate that the two halves of the LOT measure the same const ruct of optimism, but the positive half or the optimism index does thi s more adequately. The two-factor solution was probably caused by diff erence in the direction of item wording rather than multidimensionalit y. Therefore, the scale should be treated more appropriately as unidim ensional for the reason of parsimony.