Presentation on theme: " A low frequency character ever occurred under more varieties of words or environments would be recognized more easily, even its frequency is kept balanced."— Presentation transcript:
A low frequency character ever occurred under more varieties of words or environments would be recognized more easily, even its frequency is kept balanced. Models of lexical access that emphasize sub-lexical processes or interactions between levels below lexicon itself did not take into consideration of the current findings. Abstract _________________________________________________________________________________________________ Character frequency is confounded by character's ability to combine with others to generate different words. Compared to characters with lower frequency, characters with higher frequency generate more different words embedding them. To investigate their effects on character lexical decision and naming, character frequency and number of different words embedding a particular character with character frequency balanced were simultaneously manipulated in this study. Ninety college students participated. A two-way nest design analysis of variance was conducted. Results showed that besides character frequency effect, number of different words generated from a low frequency character exhibited a significant facilitating effect. _____________________________________________________________________________________________________________________________________ Mean latencies and error percentages (in parenthesis) for conditions with different character frequencies and numbers possible words embedding for lexical decision and naming Lexical decision Naming Number words generated Number words generated Frequency Large Medium small Large Medium small Experiment 1 (N=45) (N=45) High (1.36) (1.91) (1.10) (2.04) (2.32) (2.85) Low (2.42) (2.98) (5.02) (4.84) (4.80) (9.61) Very Low (9.31) (12.85) (19.99) (22.20) (19.76) (27.97) Experiment 2 (N=32) (N=32) High-Mid (0.85) (2.13) (1.71) (3.55) (5.97) (4.26) Low-Mid (1.56) (2.84) (3.69) (3.84) (7.25) (3.27) Three factors including character frequency, number different words a character generates, each designed as within subjects and between items, were manipulated as a nested factorial to be evaluated their effects on the RTs of lexical decision and naming. Two experiments manipulating different ranges of character frequency were evaluated by participants from different universities in Taiwan. Character Frequency Effect Confounded by Number of Different Words a Character Generates Jei-Tun Wu, Ph.D. Si-Cyun Yang Department of Psychology, National Taiwan University, Taipei, Taiwan Method Research background Result Conclusion Materials Presented at the 13th ICPEARL, Oct. 9-11, 2009, Beijing, China Reference Liu, I. M., Wu, J. T., & Chou, T. L. (1996). Encoding operation and transcoding as the major loci of the frequency effect. Cognition, 59, Schreuder, R., & Baayen, R. H. (1997). How complex simplex words can be. Journal of Memory and Language, 37, It is intuitive that any cognitive tasks that encapsulate word recognition should be sensitive to the changes of word‘s occurrence frequency. As a result, character frequency has long been demonstrated as the most effective factor affecting character recognition. (Liu, Wu, & Chou, 1996). A character (e.g., 菜, cai4, 'vegetable') can combine with others (e.g., 單, dan1, ‘bill’; 鳥, niao3, ‘bird’; 香, xian1, ‘odor’) to constitute different words (e.g., 菜單, cai4dan1, 'a menu'; 菜鳥, cai4niao3, 'a green hand'; 香菜, xian1cai4, 'parsley'). Analyses on frequency corpora in Taiwan showed that compared to characters with lower frequency, characters with higher frequency generate more different words embedding them. (See Fig. 1). This implies that number of different words a character generates might confound with the effect character frequency exerting on character recognition. The purpose of this study is to observe the influence of number of different words those embed a target character on character’s recognition when character frequency is kept constant. Log 10 (character frequency) Number of words Fig. 1 Number of words a character generates x Logarithm of character frequency scatter plot about 5000 characters Lower bound and average (in parenthesis) number possible words a character generates for different conditions of character frequencies character number possible words embedding frequency high medium low Experiment 1 high frequency (536) (262) (96) low frequency (55) (34) (10) very low frequency (11) (7) (2) Experiment 2 Higher-Mid (183) (119) (59) Lower-Mid (128) (74) (45) Note: There are about 5000 different characters in all corpora. The most frequent 300, 600, 1500, or 2500 characters could account for 65, 80, 95, or 99 percentages of total frequencies, respectively. In Experiment 1, there were 180 high frequency characters sampled from those characters with frequencies ranked within 300, 150 low frequency characters sampled from those ranked between 1500 and 2500, and 150 very low frequency characters sampled from those 2500 most infrequent ones. In Experiment 2, there were 150 higher middle frequency characters sampled from those characters with frequencies ranked between 300 and 600, and 150 lower middle frequency characters sampled from those ranked between 600 and 1500.