Review of Experimental Methods in Language Acquisition Research |
|
|
| Review: |
EDITORS: Blom, Elma and Unsworth, Sharon
TITLE: Experimental Methods in Language Acquisition Research
SERIES TITLE: Language Learning & Language Teaching 27
PUBLISHER: John Benjamins
YEAR: 2010
Lyn Shan Tieu, Department of Linguistics, University of Connecticut
SUMMARY
This book aims to provide detailed, current information on methods in language
acquisition research, covering methods relevant for research on first and
child/adult second language acquisition, as well as acquisition by
language-impaired children; additionally, it addresses both spoken and sign
language acquisition. The volume is intended for anyone with an interest in
experimental work on language acquisition, from undergraduate students to more
senior researchers looking for information on specific techniques and methods.
The volume begins with a detailed introduction that outlines the goals and
structure of the book, summarizes each chapter, and offers a collection of
practical tips for researchers who are about to embark on experimental work. The
main content of the book is divided into two sections: Chapters 1-9 address
specific experimental methods, while Chapters 10-13 address comparative work
across groups. For each method covered, the author(s) provide(s) an introduction
to the method, the underlying rationale behind the task, the linguistic
variables that can be examined using the method, the subjects for which the task
is appropriate, a description of the procedure, and appropriate analyses and
possible outcomes for the method. Each chapter concludes with a list of ''do's
and don'ts'' for the reader who is considering making use of the relevant method.
In Chapter 1, Sonja Eisenbeiss discusses three methods for collecting speech
production data: naturalistic studies, semi-structured speech elicitation, and
production experiments. Naturalistic studies involving minimal researcher
interference are highly versatile and more closely approximate naturally
occurring conditions. Semi-structured elicitation techniques (such as the use of
games or pictures designed to encourage the production of particular
constructions) are useful for studying low-frequency phenomena, fine-grained
semantic distinctions, or the productivity of learners' utterances. Production
experiments use methods such as elicited imitation, speeded production, and
syntactic priming; these allow researchers to systematically manipulate
variables of interest. Eisenbeiss ultimately suggests that the researcher ought
to provide converging evidence from these three methods.
In Chapter 2, Cristina Schmitt and Karen Miller address three methods used to
collect off-line (as opposed to online or real-time) comprehension data. The
truth value judgment task involves testing subjects' ability to match
interpretations of target sentences to carefully controlled scenarios presented
via stories enacted with toys, video clips, or pictures. The authors discuss the
importance of controlling factors that might influence how a subject responds to
the test items (e.g. including carefully chosen control and filler items). The
picture matching task involves having the subject choose the picture that best
matches the target sentence or phrase. Variations on the task can differ in
terms of the number of pictures presented, as well as whether all pictures are
initially visible to the subject. The act-out task involves presenting sentences
that the subject is asked to act out; this task is the most open-ended of the
three off-line tasks, lacking the forced choice component. The authors offer an
overview of insights from previous studies that have made use of these three
methodologies.
In Chapter 3, Antonella Sorace discusses magnitude estimation as a method for
collecting off-line judgment data. In the magnitude estimation task,
participants are presented with a modulus stimulus exemplifying a particular
dimension, and asked to express the magnitude of the characteristic with a
number. A series of stimuli are then presented, which vary in intensity;
participants must assign each of these a number relative to the standard
stimulus. Sorace discusses the advantages of magnitude estimation over more
conventional methods of collecting acceptability judgments, perhaps the most
notable of which is that the method is more sensitive to gradient judgments,
since participants are free to use whatever values they wish to rate a given
test sentence against the modulus. Sorace also discusses treatment of data
collected via magnitude estimation, including the need for normalization before
statistical analysis. A noted advantage is that the data yield interval scales,
and can thus be subject to a full range of parametric statistics.
In Chapter 4, Elizabeth Johnson and Tania Zamuner address three techniques that
test the receptive language abilities of young children. The visual fixation
procedure involves habituating participants (typically between 4 and 20 months
of age) to audio-visual stimulus pairings; looking times to test trials can then
reveal infants' ability to discriminate between old and new sound or word-object
pairings. The headturn preference procedure relies on the observation that
infants (six to nine months of age) typically listen longer to grammatical (or
frequent) than ungrammatical (or infrequent) constructions. The preferential
looking procedure is a versatile paradigm in which children's visual fixations
in response to visual stimuli are recorded. Included among the detailed
descriptions of the methods are figures depicting idealized data sets.
In Chapter 5, Judith Rispens and Evelien Krikhaar discuss the use of
event-related potentials (ERP) in language acquisition research. The ERP
methodology allows researchers to observe brain responses to language stimuli
(i.e. voltage fluctuations in the brain's electrical activity that correspond to
the processing of linguistic stimuli). The authors offer a detailed overview of
studies that have made use of ERP to investigate auditory, semantic, and
syntactic processing. Compared to other neuro-imaging techniques, the ERP
methodology is child-friendly, non-invasive, less expensive to carry out, and
not highly demanding on participants. The authors also note certain challenges
of the method, particularly when testing very young children, but offer helpful
suggestions to circumvent or minimize these challenges.
In Chapter 6, Julie Sedivy addresses the eyetracking technique, which involves
continuous monitoring of subjects' eye movements (or saccades), which are
assumed to reflect shifts of attention in response to linguistic stimuli. Sedivy
provides an overview of areas of research that have made use of eyetracking,
such as spoken word recognition and syntactic ambiguity resolution. The method
is adaptable for use with almost any subject with normal vision and hearing, but
challenges arise when using the method with infants and young children. Sedivy
offers a discussion of the development of appropriate stimuli for different
populations (adult vs. child, monolingual vs. bilingual), the different kinds of
equipment one might use, and also a number of relevant measures of eye movement
data (e.g. latencies for first fixation, number of fixations over the course of
a trial, total fixation time, etc.).
In Chapter 7, Theodoros Marinis addresses on-line processing methods, which
measure participants' automatic responses to language stimuli as they are
presented. In a word-monitoring task, participants hear a word and then listen
to sentences, pressing a button if they hear the earlier word; this method is
often used to investigate sensitivity to ungrammaticality. In a self-paced
reading/listening task, participants read or listen to sentences word-by-word by
pressing a button; this method is used to investigate phenomena such as
processing of temporarily ambiguous sentences. Cross-modal priming involves
aural presentation of a sentence, after which participants must, upon seeing a
word or picture, respond by pressing a button as fast as possible; this method
has been useful for investigating structures involving dependencies between two
constituents. The fourth method combines self-paced listening and picture
verification; participants see a picture on a computer screen, listen to a
sentence word-by-word by pressing a button, and then indicate whether the
sentence matches the picture. This method has been used to investigate phenomena
such as the processing of English active and passive sentences. Marinis also
discusses the advantages and disadvantages of exploiting on-line measures of
language comprehension.
In Chapter 8, Lisa Pearl discusses the use of computational models to simulate
the language acquisition process; such computational modeling can be
particularly useful in cases where the data being modeled are difficult to
obtain experimentally. Pearl discusses the kinds of questions that can be
addressed through modeling, as well as parameters of evaluating the model's
contribution to language acquisition (for example, a formally sufficient model
''learns what it is supposed to when it is supposed to from the data it is
supposed to'' (p. 166)). Pearl provides examples of acquisition problems that
modeling has been applied to, such as phoneme identification and morphological
learning. She also discusses some crucial components of model designing, such as
empirical grounding of the model (ensuring the model incorporates
psychologically plausible algorithms), and deciding which variables or
''parameters'' to focus on (and which to abstract away from).
In Chapter 9, Jan Hulstijn discusses measures of language proficiency in the
context of second language acquisition research. Hulstijn introduces some key
psychometric concepts (validity, reliability, discrete point tests vs.
integrative tests, direct vs. indirect testing), and addresses four types of
language proficiency tests. Vocabulary tests can address the number of words
that speakers know as well as how well they know them; these tests can vary
along certain dimensions (e.g. whether they measure receptive or productive
knowledge). Sentence imitation involves having the participant repeat stimulus
sentences orally, and in particular measures proficiency in segmenting and
parsing spoken sentences. The cloze test involves presenting a text that
contains words that have been replaced with gaps; the participant must then fill
in these gaps. Elicited production methods involve eliciting speech from
participants. The chapter also includes an example of how to measure proficiency
in a second language acquisition study.
In Chapter 10, Sharon Unsworth and Elma Blom address the comparison between
child second language learners, adult second language learners, and child first
language learners. The authors begin by discussing how to make the distinction
between first and second language child learners, as well as second language
adult learners. The task of defining the groups of interest is clouded by the
numerous definitions that exist in the literature; for example, various
definitions of child second language acquisition have been proposed, revolving
around varying ages from some time after birth to puberty. The authors stress
the importance of conservative and consistently applied criteria, which must be
chosen based on the goal of the research. The authors then discuss in turn
maturational effects, transfer effects, input effects, and provide a discussion
of some methodological issues relevant to comparing different groups of learners
(e.g. determining age of first exposure, controlling for cognitive development
and/or proficiency, controlling for quantity and quality of input).
In Chapter 11, Johanne Paradis discusses how to make comparisons between
typically developing child learners and children with specific language
impairment (SLI), looking at both monolinguals and bilinguals. The bulk of the
chapter is devoted to a discussion of various methodological issues, such as
considerations for comparing population groups (for example, how to match groups
and control for variation so as to best investigate the relevant between-group
differences in the target variable). She also discusses how to create a
three-group matched design study, and how to calculate mean length of utterance
(MLU) for the purposes of language-level matching. Finally, Paradis discusses
comparison studies of bilingual children and children with SLI, including some
important considerations that arise when bilingual children are included in a
comparison study (e.g. whether the children are simultaneous or sequential
bilinguals, consideration of possible cross-linguistic transfer and code-mixing,
etc.).
In Chapter 12, Anne Baker and Beppie van den Bogaerde offer a discussion of how
to compare deaf learners with other groups. They begin by introducing some
theoretical issues that arise in sign language acquisition research; for
example, input conditions can vary depending on whether deaf children are born
to hearing or deaf parents, whether they receive signed input, and whether this
input comes from native signers. The authors also discuss applied issues, such
as the development of policies for family guidance programs, and the effects of
cochlear implantation on the development of deaf children. The bulk of the
chapter is devoted to methodological issues that arise in the study of deaf
language acquisition, including design requirements and procedures (in
particular, the challenge of finding a homogeneous population of deaf children).
The authors also discuss issues relevant to data analysis and presentation, and
offer information about transcription methods and database construction.
In Chapter 13, Hugo Quené offers a general introduction to methodology and
statistics as used in language acquisition research. He introduces the reader to
the concept of hypothesis testing, and discusses how studies can differ (for
example, how experimental designs containing one independent and one dependent
variable differ from designs that vary factors within subjects). He then
addresses the issue of validity and the challenges of eliminating nuisance
variables and confounds. Quené also provides a discussion of data analysis,
addressing issues such as level of significance, Type I errors (regarding a null
effect as significant) vs. Type II errors (false negatives), effect size and
statistical power. Quené further expounds on these issues by providing a section
devoted to frequently asked questions about these very issues, and offers tips
for dealing with challenges (such as increasing relative effect size to
compensate for a smaller sample size).
EVALUATION
This book is an excellent manual for the language acquisition researcher, and
would constitute an ideal reader for courses on experimental methodology in
acquisition research. It provides a rich and extensive overview of various
methods that have been used in the field of language acquisition, and offers, in
a very practical fashion, the advantages and disadvantages of each method. The
target audience is meant to include both beginner and experienced researchers;
in this respect, it certainly succeeds as advertised. For the beginner
researcher, the book provides an excellent introduction and overview of some
commonly used methodologies, and very helpfully explains the appropriateness of
each method; for the experienced researcher, the book rises to the occasion in
providing a refresher on relevant methodologies. The greatest contribution of
the book is that it compiles extremely useful and relevant information on
various methodologies within a single source.
In covering as much as it does, however, one should note that the book is
(naturally) somewhat limited in the amount of detail provided for each
methodology. This book is in essence a handbook, and while it provides extremely
useful and relevant information in a readily and easily accessible form, it is
not meant to provide exhaustive coverage of all the details behind each
methodology. For that, one must look to additional sources. It is a merit of the
book, however, that each article does indeed point the reader to plentiful other
sources, which include not only methodologically-oriented works that offer more
focused detail about the methods themselves, but also numerous previous
acquisition studies that have made use of the methods in question. These
references are provided throughout the discussion in each chapter, as well as in
extensive reference sections at the end of each chapter. The book, then,
provides an excellent basis of knowledge, but ultimately must direct the reader
to other sources for further detail.
Another limitation that arises from its conciseness as a handbook is that in
many places it does not provide more detailed examples of experimental
conditions. Each chapter does a good job of adequately describing the relevant
procedures, but one must look to the references cited therein to see exactly how
one would apply the method described (e.g. for examples of particular test
items, instructions to participants, picture stimuli, dialogues, etc.). Each
chapter adequately describes in prose various methodological points pertaining
to relevant procedures, but it would have been helpful in many places to see an
example of an actual test condition. These are not completely absent from the
book, however; Sorace's chapter on magnitude estimation, for example, offers an
example set of instructions that walks the reader through the crucial components
of the experimental set-up, from the calibration session, to the practice
session, to the actual test session (pp. 63-65). Such an explicit example offers
the reader a very helpful ''tour'' of the method, demonstrating very clearly how
to apply the various methodological points raised throughout the rest of the
chapter. Another helpful example is found in Johnson and Zamuner's chapter on
methods of infant testing, where the authors provide graphs depicting idealized
data sets, which allow the reader to visualize target differences between
conditions.
A notable merit of the book is that it does not restrict itself to any
particular theoretical approach to language, and moreover, the methods that it
covers collectively address research in a very broad range of linguistic
subfields and research topics, including (but not restricted to): phonological
development, grammatical feature specification, binding principles, grammatical
agreement, morphology, quantifier interpretation, optionality, language
attrition, language contact, word learning, phonotactic sensitivity, phonemic
contrasts, auditory processing, lexical/semantic/syntactic processing,
reference, ambiguity resolution, pragmatics, pronoun/anaphora resolution, etc.
As such, almost any language acquisition researcher will find some issue of
interest in the volume.
In short, this volume succeeds in its goal of providing students and researchers
with very helpful and hands-on information about frequently used experimental
methods in language acquisition research.
ABOUT THE REVIEWER
|
| |
ABOUT THE REVIEWER:
Lyn Shan Tieu is a PhD candidate in the Department of Linguistics at the
University of Connecticut. Her research interests include child language
acquisition, theoretical semantics, and pragmatics. Her present research
includes investigations of negative polarity item licensing in
interrogative environments, as well as child first language acquisition of
negative polarity phenomena. Other work involves investigating syntactic
development in bilingual children. |
|
|
