For students who don’t read very well whether the word is best case or worst case shouldn’t matter Prefixes should help better readers That is, for students at higher reading levels, rea[r]
Carnegie Mellon How often are prefixes useful cues to word meaning? Less than you might think! Jack Mostow *, Donna Gates *, Gregory Aist *, and Margaret McKeown + Project LISTEN (www.cs.cmu.edu/~listen) *Carnegie Mellon University +LRDC, University of Pittsburgh Funding: IES 15th Annual Meeting of the Society for the Scientific Study of Reading, June, 2009 Project LISTEN 11/12/21 Carnegie Mellon Research question Conventional wisdom is to not give instruction on morphology until perhaps grade four However, kids encounter words with prefixes As part of the IES-funded vocabulary grant, we wanted to take opportunistic advantage of prefixes: when prefixes occur, explain them to help vocabulary How often such opportunities occur? That is, how often are prefixes good cues to meaning? What happens when they do? That is, what is the effect of reliable prefixes on reading times? Project LISTEN 11/12/21 Carnegie Mellon Outline What’s a prefix? Linguistically Instructionally For this talk How reliable are prefixes as cues to meaning? What is the effect of prefixes on reading times? Project LISTEN 11/12/21 Carnegie Mellon What’s a prefix? A linguistic definition affix Any element in the morphological structure of a word other than a *root(1) E.g unkinder consists of the root kind plus the affixes un- and –er … Affixes are traditionally divided into prefixes, which come before the form to which they are joined; *suffixes, which come after; and *infixes, which are inserted within it Others commonly distinguished are *circumfixes and *superfixes P.H Matthews, The Concise Oxford Dictionary of Linguistics, Oxford UP, 2007 p 11 Project LISTEN 11/12/21 Carnegie Mellon What’s a prefix? An instructional definition White, Sowell, and Yanagihara (1989) suggest the following definition of prefix: it is a group of letters at the beginning of a word misspell it changes the meaning of the word mis- = incorrectly spell incorrectly when you remove it, a word is left misspell Project LISTEN 11/12/21 What’s a prefix? For this talk: The ones to teach Carnegie Mellon White et al (1989) analyzed English words in printed school materials They found that the 20 most common prefixes make up 97% of prefixed words in English school texts The most frequent prefixes make up 76% of these words Stahl and Nagy (2006) advise teaching the most common prefixes: un6 non2 re7 in- (im-) into in- (im- il- ir-) not over- too much dis9 mis5 en- (em-) Project LISTEN 11/12/21 Carnegie Mellon A note on terminology In some places in this talk we will use these terms to avoid undesired implications of “prefix” and “stem” / “root” Head: letters at the beginning of a word Tail: rest of letters in the word Semantically Reliable: meaning of head is represented in the definition of the word Project LISTEN 11/12/21 Carnegie Mellon Outline What’s a prefix? Linguistically Instructionally For this talk How reliable are prefixes as cues to meaning? What is the effect of prefixes on reading times? Project LISTEN 11/12/21 Carnegie Mellon How reliable are those nine prefixes as cues to word meaning? Materials: WordNet definitions and relations Project LISTEN story vocabulary American National Corpus vocabulary Methods: Calculate percentage of word types for which one of the nine most frequent prefixes is semantically reliable in a word’s definition Head: NONswimmer Tail: nonSWIMMER Project LISTEN 11/12/21 Carnegie Mellon Head that looks like prefix may not be displeased: not pleased; experiencing or manifesting displeasure dismay: fear resulting from the awareness of danger; the feeling of despair in the face of obstacles; fill with apprehension or alarm; … Prefix Prefixed Example Non-Prefixed Example Meaning of Prefix dis displeased distance not, undo en encourage enough give some property to or cause in (il, ir ,im) immigrate, illegal innocent illness a) into b) not mis misspell mister incorrect non nonfat (none) not over overgrow overtly too much re repaint really again un (um) unnecessary unite not, undo Project LISTEN 10 11/12/21 ... opportunistic advantage of prefixes: when prefixes occur, explain them to help vocabulary How often such opportunities occur? That is, how often are prefixes good cues to meaning? What happens when... Project LISTEN 11/12/21 Carnegie Mellon How reliable are those nine prefixes as cues to word meaning? Materials: WordNet definitions and relations Project LISTEN story vocabulary American National... How reliable are prefixes as cues to meaning? What is the effect of prefixes on reading times? Project LISTEN 13 11/12/21 Carnegie Mellon What is the effect of prefixes on reading time? Compare