Complexity and Task-Complexity

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The Oxford Advanced Learner’s Dictionary defines complexity as ‘the state of being formed of many parts’ (Oxford Advanced Learner's Dictionary, 2020). The general understanding is that an action or process is complex when it is difficult to understand and requires additional resources that are beyond one’s potentials, as opposed to a simple one that doesn’t. Thornbury (2006) defined complex language in SLA as that which ‘uses structures more typical of advanced learners than of lower level learners’ (p. 40). He listed the use of subordination including complex sentences, pronouns for back references, more lexical verbs than linking verbs, more content words than function words, and conjunctions as factors that determine complexity.
Long (2015) defined task-complexity in TBLT as “inherent, unchanging qualities of a task that make it more or less challenging than another task at a given moment in time” (p. 232). That is, task complexity is not external to task, but is inherent to the task itself. Relative complexity of different tasks or task types is the result of the cognitive demands they make on the language user. Long (2015, p. 227) lists valence, frequency of occurrence, learnability, and complexity and difficulty as criteria to judge the relative task-complexity. Task complexity is understood and manipulated in terms of the cognitive demands tasks make on the language user. Manipulation of task complexity influences the complexity of language output (Thornbury, 2006, p. 40). Assuming that increasing levels of task complexity improves specific characteristics of language output, task complexity can be manipulated to support interlanguage development (Long 2015, p. 231). Task sequencing and grading are used to help develop learners’ interlanguage. Different aspects of task complexity are discussed in the following sections. 

References 

Long, M. (2015). Second language acquisition and task-based language teaching. Chichester: Wiley-                                Blackwell.  

Oxford Advanced Learner's Dictionary. (2020, March 2). Retrieved from Oxford Learner's Dictionaries:                              https://oxfordlearnersdictionaries.com/definition/english/complexity?q=complexity 

Thornbury, S. (2006). An A-Z of ELT: A dictionary of terms and concepts used in English Language                                 Teaching. Oxford: Macmillan.

 

Communicative Tasks for CBSE Class X Skills Assessment

Task 1: Pair discussion task designed to assess candidates’ speaking ability

Help Vijaya

Read the instructions carefully before you begin speaking. You can make notes and use them while discussing. You will get 3 minutes to discuss.

Your friend Preethi’s mother is a bank manager. Recently she is transferred from Delhi to your town. Preethi secured admission in your college, in your course. But she has no idea about the subjects of study and examination pattern in your college. Since classes have already started, and first term examination is approaching, she wants to know more about the subjects you study, their content in short, and the kind of questions that appear in the examination. Share these details with her to help her deal with this situation.

This is a personal information exchange task where test-takers share their own information.

Task 2: A task using ‘performing actions based on listening’

Building Origami Cat Face

Listen to the audio carefully and follow the instructions.

Transcript of audio:

Step 1: Take a square-shaped piece of paper.

Step 2: Fold the paper from corner to corner, diagonally- this is fold 1

Step 3: Fold the it again from corner to corner diagonally- this is fold 2. Press the folds firmly and open fold 2.

Step 4: Fold the top pointy end about ¼ of the way down- this is fold 3.

Step 5: Fold the other two corners upwards at about 5-degree angles- this is fold 4 (draw the angle on board)

Step 6: Turn the paper around and draw eyes, nose, mouth and moustaches. Your Origami cat face is now ready!

This is a very simple task to assess listening skills based on the action that follows.

Task 3: An example reading task to assess discourse structure is given below.

Assessing formal discourse structure [Adopted from (Krishnan, Testing Reading, 2012)]

Read the following paragraph. Then divide it into three paragraphs with the following headings: 1-New Immigration System, 2-Indians May Benefit, 3-Other Foreign-Policies.

U.S. President Donald Trump has proposed a merit-based immigration system. It could benefit highly-skilled Indian workers. But it prevents them from sponsoring their extended families. It is part of an aggressive plan which he said will serve national interest. However, there was no reference to the H-1B visas in the proposal which Mr. Trump sent to Congress on Sunday. It is the most sought after visa by Indian IT professionals. Therefore, it is assumed that Indians would benefit from the new policy. Trump administration has more in their wish list. One of them is overhauling the country’s green-card system. Another is the funding of a controversial border wall along the U.S.-Mexico border. A third is said to be a crackdown on unaccompanied minors entering the country.

Task 4: A writing task.

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You have received a new bicycle as a birthday gift. Therefore, you want to sell your old blue coloured bicycle which is in good condition. You recently got it serviced, and replaced both the tyres. Write an advertisement for your school notice board in about 40 words. 

3 Basic Problems of Language Assessment

The three basic problems of assessment are

1. inference
2. prediction and
3. generalisation.

1. Inference

Inference is what we do with the performance of a test-taker. We make inferences about the language abilities of the test-taker based on how the test-taker has performed on the assessment in question. The problem is that to make this inference, we make a lot of assumptions about language and language performance. We assume that language performance comes from underlying language competence or underlying language abilities. We also assume that language abilities have particular structure, and that different language abilities interact with each other. Based on these assumptions, we design our tests to systematically sample test-taker's language. This sample is used as our raw material to make inferences about the underlying language competence or abilities.

The real problem is that we do not for sure know what is the relationship between performance and abilities/competence or how abilities are structured or how they interact with each other. All these questions are still not satisfactorily answered. 

2. Prediction

Prediction is to say in advance how language abilities will be used in future, in actual situations in real time. A good test will have high potential to predict actual performance. Abilities will interact with other performance conditions like physical conditions, affective factors, etc. during performance. Therefore, prediction has to consider these influences.

The problem is that if a test cannot make accurate predictions or if it makes wrong predictions, the decisions made based on the test will have serious consequences.

3. Generalisation

Generalisation is about applying the prediction to other contexts of language use as well. This is an important quality since a language test must be able to talk about a learner's language use in many situations and language use contexts. Otherwise a test has very limited relevance. Tests generally characterise different contexts so that we know what is different in various contexts. Using this information, we can apply the prediction based on a test to other contexts too.

The problem is when a test doesn't have the capacity to generalise. The test will be highly parochial, and its relevance will be too localised.

A larger problem

Each of the above problems conceptualise language sampling in different ways. Therefore, no single approach to language sampling is possible. With any particular approach, we cannot solve the problems mentioned above. These are the approaches available today which have their own independent focuses.

1. Abilities approach: This approach uses a model of communicative competence. Abilities underlie performance. Therefore this approach tries to build tests to elicit performance based on particular underlying abilities. Here language processes and contexts are treated as secondary extensions.

2. Processing approach: Processing approach gives centrality to language processing. Therefore, real-time language processing in communication is the focus of assessment. Tests will assess how well test-takers can handle the pressures of communication online. In this approach, abilities play only a secondary, service role. Therefore, assessment will focus on a sampling framework that looks at performance conditions. Generalisation thus will be to other language use contexts that use the same kind of language processing only. Again, this is limited.

3. Contextually driven approach: In this approach, difference between different contexts is the focus. Assessment is focused on the characteristics of contexts. Test sampling therefore focuses on covering a range of contexts so that generalisation of prediction is meaningful to those contexts.

Solution to these problems

1. Develop a model of underlying abilities

2. Develop direct performance tests combining performance and contextual problems

The first solution could be systematic in portraying language abilities. This would align with empirical methods used today in measuring abilities. Therefore, this approach could further the existing scholarship in the field. The process would be defining language constructs, then gather data to assess constructs, then assemble effective tests.

Its problem is that is presents a static picture of proficiency. Since it assumes that there are underlying abilities, and is trying to uncover them, it is a difficult endeavour especially because we are not sure of what these underlying abilities are, or what are their connections with performance!

The second solution has greater predictive quality because of the restricted situations it deals with. It emphasises context validity by looking into characteristics of contexts and performance. 

But the problem is that it deals with limited number of contexts or domains. Validation depends on needs analysis, which in turn depends on assessment, and vice versa. It works pretty much like ESP (English for Specific Purpose) tests. Generalisation is limited. Moreover, there is little underlying theory to explain the differences in contexts and performance in relation to abilities.

Therefore, the former 'interactive ability' model seems to be the better choice in terms of prediction and generalisation capacities. 

International English Language Testing System (IELTS)

IELTS examination is conducted by the British Council. The test score is used for the purposes of Study, Migration and Work. It’s a high stakes gatekeeping examination that screens people for the aforementioned purposes. It measures the English language proficiency of people who want to work or study in an English speaking country. It awards one of nine grades to test-takers, based on their performance. The test is available in two separate versions- one for academic purposes, and another for general training. IELTS accepts all native speaker versions of English- British, North American, New Zealand and Australian English. Assessment covers all four skills (listening, speaking, reading and writing).  The test promises to avoid biases through careful planning and execution. The test can be taken at any test centre across the world on about 50 different dates a year.

IELTS Academic and IELTS General Training versions
The IELTS Academic version is for people who wish to pursue higher education or to register for professional services in an English speaking country. The test content is academic in nature. The General Training version of the test is for those who go to an English speaking country for intermediate education, work experience or some training programme. Australia, Canada, US and UK take this test as the criterion for allowing migration. The test content is designed to test basic survival skills in everyday living situations.

The test is organized as two parts on two days. Listening, reading and writing tests will be completed on the same day in a 2 hours and 45 minutes’ continuous test. Speaking test is conducted within two weeks before or after this according to the plan of the test centre.
IELTS Listening

Listening test is for 30 minutes. There will be four recordings. Two of them will be on everyday social contexts- a conversation and a monologue. The other two will be on academic subjects or educational context- a conversation and a monologue. Assessment will be based on factual information, opinion and attitudes of speakers, purpose of utterances grasped and the ability to grasp development of ideas. There will be 40 questions. MCQs, matching, plan/map/diagram labelling, form/note/table/flow-chart/summary completion, sentence completion, etc. are the types of tasks available. Each question carries one mark.

MCQs will have three or more options to choose from. Global comprehension or comprehension of specific points is used to test a wide range of skills. Matching questions test the candidate’s abilities to relate and connect facts in the listening passage, to listen for details, to follow a conversation, etc. Planning, mapping and diagram-labelling questions assess candidate’s abilities to understand and relate descriptions to visual representation, to follow spatial directions, locations, etc. Questions that use form/note/table/flow-chart and summary completion test candidate’s comprehension and attention to details. In a given outline, candidates will have to fill in the required information. In this type of questions, the instructions are crucial and have to be strictly followed to avoid negative marking. Sentence completion intents to test the candidate’s ability to identify key information in a listening text. They will have to complete the given sentence using information from the listening passage. A word limit is given and has to be strictly adhered to. Short answer questions test candidate’s ability to comprehend factual information from listing. Again, word limit applies here. Assessment is done by trained and certified markers and analysed by Cambridge English Language Assessment.

IELTS Reading
Reading has two kinds of tests- Academic reading and General Purpose reading.

IELTS Academic Reading
Academic reading test is for one hour, and has forty questions. Candidates are given three reading passages. Task types used are multiple choice, identifying information, identifying the writer’s views/claims, matching information, matching headings, matching features, matching sentence endings, sentence completion, summary completion, note completion, table completion, flow-chart completion, diagram label completion and short-answer questions. Texts used are selected from books, journals, newspapers and magazines on general interest topics. Passages can have narrative, descriptive, or discursive/argumentative style. Texts may contain logical arguments and non-verbal information. Questions are given in the same order as information appears in the text. For MCQs, four, five or seven alternatives will be given. They test global and local comprehension. Identifying information and writer’s opinion, candidates prove their ability to locate and recognize information conveyed in the text. Opinion tasks are used with argumentative tests. Matching information tests candidate’s ability to identify specific information where matching headings tests the ability to identify main /supporting ideas. Matching questions test candidate’s ability to relate information. For this, skimming, scanning and reading for detail are necessary skills. Matching sentence endings tests candidate’s ability to understand main ideas within sentences by selecting the best option to complete the given sentence. There will be more options than the number of questions raising the level of challenge. Sentence completion questions test candidate’s ability to locate specific details in a text. Completion of summary/note/flow-chart/table asks candidates to complete the given summary, etc. with information from the text. Understanding of main ideas, collocation, etc. are tested with this type of tasks. Diagram labelling asks candidates to label the given diagram based on the text. Understanding of detailed description and ability to transform information into other forms are tested with this type of tasks. Short answer question test candidate’s ability to locate specific information within the text.

IELTS General Purpose Reading
There are three sections in this one-hour general purpose reading test. Maximum score is forty marks. The first section has two or three short texts. It tests candidate’s social survival skills to retrieve information from notices, tables and advertisements. The second section is to test candidate’s skills in workplace survival. Materials used will be like job descriptions and staff training materials. The third section involves general reading with more complex structures. Descriptive and instructive materials of general nature are selected. The types of questions are the same in Academic Reading test. The difference is in the materials used which raise or lower difficulty level of the test.

IELTS Academic Writing
This is a one-hour test with two questions to be answered. First question is to describe some visual information (charts, tables, diagram, device or process) in their own words, and second question is to respond to a point of view or argument or problem. The first answer expects the use of academic or semi-formal neutral style including most relevant information from the given data. About 150 words must be written in about 20 minutes in sentences (not as broken sentences, or notes). The second answer must be focused and relevant to the question. About 250 words are expected in about 40 minutes.
Each task is assessed independently by certified examiners who are approved by British Council. Performance descriptors are clearly stated. First question is assessed on the criteria of task achievement (how well task-requirements are fulfilled), coherence and cohesion (logical sequencing and linking of ideas and fair use of cohesive devices), lexical resource (range and accuracy of vocabulary use) and grammatical range and accuracy. Second question is assessed on the same criteria except for that of task completion. It is replaced by task response which sees how the candidate develops a position in relation to the given question, how ideas are supported by evidence, etc.

IELTS General Training Writing
Like in Academic Writing, here too we have two writing tasks. The first task is to respond to a situation in the form of an informal, semi-formal or formal letter in at least 150 words in about 20 minutes. Common day to day situations will be presented. The skills needed would be asking or giving factual information, expressing likes, dislikes, needs and wants, and making requests or suggestions. Test takers’ ability to write standard letters, organize and link information appropriately, cohesively and coherently is tested. The second task is to respond to a point of view or argument or a problem. It requires at least 250 words, and candidates can take about 40 minutes. Answering might involve providing factual information, presenting a solution, justifying an opinion or an argument, evaluating an evidence, etc. General topics are used. Answering requires the use of more abstract and complex ideas than task 1. Irrelevance and short text would attract negative marks.

Assessment criteria and performance descriptors are the same as in Academic Writing test.

IELTS Speaking 
Speaking test is an oral interview with an examiner. The test is recorded for evaluation and quality maintenance. It lasts about 14 minutes. There are three parts with specific functions.

Part 1 is introduction and interview. Test taker is asked his/her name, details about family, and other familiar everyday topics to put him/her at ease and to introduce them to each other. Ability to speak of everyday topics, state opinions and experiences are tested in this part. This part takes four to five minutes.

Part 2 takes about three to four minutes. But this time, the candidate will have to speak on a given topic in detail. Candidate prepares for a minute, speaks for two and then answers interviewer’s questions. This part tests the candidate’s ability to speak coherently at length about a topic without prompts, using appropriate language. Candidate may have to speak about his/her personal experiences also.

Part 3 is a discussion about the same topic in part 2 in a general, but deeper manner. The focus of the test is on the ability to express and justify opinions and to analyse, speculate about and discuss issues. This takes four to five minutes.

Marking is done by certified IELTS examiners. Performance descriptors are prepared. Fluency refers to the ability to speak fairly continuously at a fair rate to make coherent and connected speech. Coherence refers to logical sequencing, marking stages of a discussion, narration, argument and use of cohesive devices. Lexical resource means range and accuracy of appropriate choice of vocabulary. Ability to circumlocute is also noted. Grammatical range and accuracy refers to appropriate use of grammatical resources. Length and complexity of spoken sentences, use of subordinate clauses, range of sentence structures, number of errors made and their effect on communication are the measures of grammatical ability. Pronunciation is measured by the amount of strain listener has to put in, amount of unintelligible speech and influence of L1.

Figure 1- IELTS Score band

The final score is generated by averaging individual test scores of the four skills. It ranges from 0 to 9 as shown in Figure 1. The test score has a validity of two years. 

IELTS claims to be fair to candidates of all nationalities, cultural backgrounds, genders or special needs by trialling the test questions extensively with people from various backgrounds all over the world. It assesses language skills, not specialist skills. It is not based on any particular text book or syllabus, but on general knowledge of English language and its use.  To ensure quality and safety, IELTS has established procedures to verify candidate’s identity. The tests are unique- no candidate gets the same test twice. Assessment involves double marking and has other security features. Results are available online.

The test development has the following stages.
a. Commissioning of language specialists to work on the test. Test development starts with test specifications and characteristics of four IELTS components. This team of specialists guides test writers by providing information on specific requirements, approach to test writing, and selection of appropriate materials.
b. Pre-editing is the stage where initial materials submitted by test writers are edited for topic, level of language, style, level and focus of task. Suggestions for revision are given to the writers.
c. Based on pre-editing feedback, test material is worked on and resubmitted. This material is either sent for further revision or for pre-testing.
d. Pre-testing stage gives the test to representative groups of test-takes from around the world. Information on item difficulty and ability to distinguish between strong and weak candidates is gathered. Based on this information, decisions are made whether to accept or not to accept particular materials for testing.
e. Standards fixing stage involves testing new listening and reading materials with representative test-taking groups. This ensures that the difficulty levels of the materials are appropriate to provide same measures of language ability in all band scores. Once this is done, materials are ready for use in tests.
f. Test construction and grading is the final stage. Papers for all four tests are constructed. Test construction is based on item difficulty (mean of all items and that of individual items), range of skills tested, balance of task types, range of cultural perspectives and range of voices and accents in the listening versions. Data from tests is collected to ensure accurate grading and to feed into quality improvement.

A Framework to describe Language Ability

Bachman and Palmer (1996) discusses the need to have a clear framework to talk about language ability. Since we use tasks in test in order to make inferences about test takers' language abilities, or decisions about their future, we need to demonstrate how test tasks correspond to language use tasks in real life. To do this we need a framework that could efficiently and clearly describe language task characteristics, test task characteristics, test taker characteristics and language user characteristics.

What is language use?
Language use is the creation and interpretation of meaning in discourse by an individual, or dynamic and integrated negotiation of intended meanings between two individuals. It involves multiple interactions, and is complex. It involves multiple language use situations including testing situation. Since language use is made up of interactions, we need an interactional framework.

As we can see in the figure, the inner circle has characteristics of the individual, outer circle has those of tasks and settings. They interact in language use. Thus the need for an interactional framework.

Individual characteristics are 

• personal characteristics like age, sex, nationality, resident status, native language, level and type of general education, type and amount of preparation or exposure to the given test, etc.
• topical knowledge: real world knowledge. They are knowledge structures in long term memory. This information is used by language users in the task. Some tasks presuppose certain kinds of topical knowledge.
• affective schemata: It is the affective or emotional correlate of topical knowledge. On presentation of the task, test takers assess the task using this. Affective responses are determined by affective schemata and task characteristics. 
• Language ability: The definition of language ability needs to be context specific. There is no universal definition. Our inferences will be based on this definition. This definition is known as 'CONSTRUCT DEFINITION'. The model of language ability presented here has two components. They are: 1. Language Knowledge and 2. Strategic Competence.

1. Language Knowledge

Language knowledge is what is used by strategic competence to create and interpret language discourse. It has two components: Organisational knowledge and Pragmatic knowledge. They are described in the following diagram from Bachman and Palmer (1996).

2. Strategic Competence

It is the set of metacognitive components or strategies. The elements are goal setting, assessment and planning as can be seen from the figure below from Bachman and Palmer (1996). 

 

How is metacogntive strategies used in language use and language test? The following diagram from Bachman and Palmer (1996) will tell us. 

Language Skills
Traditionally, language skills meant the four language skills- listening, speaking, reading and writing. The new understanding suggested by Bachman and Palmer is that language skill is situated in particular contexts, in specific tasks. it is not part of language ability, but is a contextualised realisation of language ability to use language in specific language use tasks. Therefore, they urge us not to think of language performance in terms of 'skills', but in terms of specific tasks or activities. Therefore, 'skill' can be better seen as a combination of language ability and task characteristics.
Advantage of this view
The advantage of this view is that the above framework can be used to design new tasks, or select existing tasks for assessment using a checklist of language abilities. See the checklist below.

This summary is from Bachman and Palmer (1996). I believe this summary is useful to you as a test designer and test user.

Characteristics of Tasks for Language Tests

Like all language learning and teaching tasks, language test tasks also have characteristics. Yes. But why are we talking about task characteristics in the context of tests? We are talking about the characteristics of test tasks for the following reasons.

Uses of Task Characteristics

• Knowing the characteristics of tasks will help us link test and non-test tasks better. That is, if we know the characteristics of a task, we will be able to see if test tasks reflect non-test tasks. In other words, we could ensure that the task we use in a test is much like a task in real life situations. 
• Knowing the characteristics of tasks will give us information about what language ability of the test-taker is engaged while performing test/non-test tasks.
• Knowing the characteristics of tasks will help us establish authenticity of test tasks. If the test task characteristics correspond to Target Language Use (TLU) task characteristics, we have an authentic test task.
• If we know task characteristics, we will be able to control them while designing test tasks.

Test must be a clear, transparent process. In testing, it is important that the test taker must understand how to perform, what performance is expected, how the performance will be rated and how the result will be used. 

In order to talk about tasks characteristics in the context of language assessment, we must first define language use tasks. Language use tasks are the tasks used in language tests to gather information about the test-taker's language abilities. They are situated in particular contexts, goal oriented and involve active participation of test taker/s. 

TLU domain is the set of language use tasks that the test-taker might encounter outside the testing situation, to which we want to generalize our inferences about language abilities/skills. 

For our purposes, we can look at language use as a set of language use tasks, and language test as a procedure to elicit language use instances from which inferences can be made about test-taker's language abilities. 

Characteristics of Test Tasks

Task characteristics have very clear influence on task performance. When our intention is to elicit best performance from test-takers, we ought to consider task characteristics so that the test tasks are best suited to elicit their best performance. Especially when each test task is a bundle of characteristics, we need to have a framework for clear understanding. Bachman and Palmer (1996) proposes the following framework to understand and use task characteristics for test development and design.

The framework intends to help us base test tasks on TLU tasks, ensure comparability of test and non-test tasks, and ensure authenticity. The elements of the framework are:

1. Setting

Setting implies physical circumstances. It has three elements.

• Physical settings (place, light, furniture, etc.), 
• Participants (administrators, other participants in group tasks, etc.) and 
• Time of task (conducted at what time, when test-takers are fresh/tired, etc.)

2. Test Rubric

Test rubric talks about structure and procedures of the test. Elements are:

• Instructions: explicit so that test-taker is informed how to take the test, how it is scored, and how scores are used; Language of instruction, its presentation and specification of procedures must be conducive. 
• Structure: how parts are put together to form the entire test.
• Time allotment for each item, and the entire test.
• Scoring method: Criteria of correctness, scoring procedure and explicitness of both of these must be informed clearly.

3. Characteristics of Input

Elements are:

• Format
• Channel- aural, visual or both
• Form- language, non-language or both
• Language- native, target or both languages
• Length of input texts
• Type of input- item or prompt
• Degree of speededness- how fast the testee must process the input
• Vehicle- how the input is delivered: live, reproduced or both
• Language of input- organisational (grammar, vocabulary, syntax, morphology, etc.) and pragmatic (functional and sociolinguistic) characteristics, and topical (personal, cultural, social information) characteristics.

4. Characteristics of expected response

Elements are:

• Format
• Type of response expected: selected, limited production or extended production
• Degree of speededness- time available/needed to process
• Language- native, target or both languages

5. Relationship between Input and Expected Response

Elements are: 

• Reactivity: how input or response directly influences subsequent input/responses
• reciprocal tasks: with an interlocutor- has feedback and interaction
• non-reciprocal tasks: no feedback or interaction
• adaptive tests: new development. Subsequent tasks are varied in difficulty depending on previous response
• Scope of relationship: The amount of language to be processed in order to respond as expected
• broad scope- like in a prompt question
• narrow scope- needs to process only limited amount of available input.
• Directness of relationship: whether expected response is based directly on input or also on other background information/knowledge
• Direct
• Indirect

Application of this Framework: To compare TLU and test task characteristics, and to create new tasks by assembling different task characteristics.

Summary from Bachman and Palmer (1996)

Three types of task planning on Fluency, Accuracy and Complexity in L2 oral production

"The Differential Effects of Three Types of Task Planning on the Fluency, Complexity, and Accuracy in L2 Oral Production"- Paper by Rod Ellis, published in Applied Linguistics 30/4, 2009. Available at this LINK to download.

This paper by Rod Ellis is an excellent summary of research on the effects of planning time in L2 oral production till 2009. Ellis puts the research till date in perspective and outlines questions for future research. A summary with comments is given below. I am adding my comments in Italics wherever appropriate. Relevant references are copied from the original paper  and given at the end of this post for your quick reference. 

Research on the effects of planning time on L2 oral production informs the methodology of task-based teaching for improvement.

Three kinds of planning are distinguished by Ellis (2005). They are Rehearsal planning, Strategic planning and Within-task planning. 

Rehearsal and Strategic are both Pre-task planning which is done before the learner actually does the task.

Rehearsal planning is when the learner rehearses the entire task before performing the task a second time. 

Strategic planning lets the learner plan what language and content to use during the task, but doesn't let the learner rehearse the task.

Within task planning is when planning takes place during the performance of the task. There are two kinds- Pressurised and Unpressurised. Pressurised planning has a specific time limit. Therefore, learners must strive to finish the task within this constraint. This is otherwise known as pressurised online planning. Unpressurised planning provides unlimited time to complete the task. This leads to careful online planning. 

Three aspects of language production are looked at to see the the effect of planning time on them. They are, accuracy, fluency and complexity. They constitute a learner's language proficiency. These three terms are defined by Skehan (1998) and Skehan and Foster (1999). Fluency is the capacity to use language in real time, complexity is the capacity to use more advanced language and Accuracy is the ability to avoid error in performance. In practice, however, researchers develop and use operational definitions to serve the goals of their research. This is problematic when it comes to comparison of different studies. 

The framework developed by Skehan (1998) speaks of two systems possessed by language speakers. They are rule-based and memory-based systems. Rule-based system consists of the underlying rules and patterns of language. Memory-based system consists of chunks of language or formulaic sequences which are readily accessible for use. The difference between these two is in terms of processing load. The former requires large amounts of attentional resources to process, while the latter requires much less resources. Language performance involves the use of both in a variable manner depending on the requirements and demands of language processing at the time of production. This has three implications. Firstly, this implies that proficiency is a flexible phenomenon which adapt according to the conditions available during performance. Secondly, if one learner lacks in one of the systems, he/she can compensate that shortcoming using the other. Thirdly, when the situation demands greater dependence on one system, some aspects of performance might be affected. For example, when rule-based system is heavily used during a performance for the sake of structural accuracy, fluency of speech might get affected. Individual differences can also affect performance in this manner. 

1. Studies in Rehearsal Panning Time

Rehearsal planning give the learner an opportunity to perform the entire task prior to actual performance that is counted. For the same reason, rehearsal planning time is not practical in testing practice. Ellis cites three studies: Bygate (1996), Gass et.al. (1999) and Bygate (2001). Two major questions are asked in these studies.
i. Does task repetition have any effect on the performance of the same task?
All three studies produced evidence for beneficial effect of task repetition on the performance of the same task.
ii. Does task repetition have any effect on the performance of a new task?
All studies reported that that there is no transference of effects to new tasks, even when the new tasks are of the same type as the rehearsal task.
Which aspect of performance is affected by rehearsal?
Fluency and complexity are the most influenced aspects as reported by all three studies. Bygate used 10 week gaps to see if the effect is due to immediate recall, which is not. Accuracy was found to have no/little effect on performance.
Acquisition-Performance connection
Since the studies showed that there is no transference of the effect to new tasks, it implies that performance in L2 does not lead to acquisition. Or, to lead to acquisition, learners need to get feedback on the initial performance to enable 'noticing' and successive acquisition. An interesting study reported is Sheppard (2006)- an unpublished PhD thesis from the University of Auckland. This study reports the feedback intervention mentioned above.

Thus we could conclude that task repetition affects performance. But when used along with other tools like feedback, it could even lead to acquisition, and positive influences on all three aspects of performance. 

2. Studies in Strategic planning time

Ellis cites 19 studies here. He uses four parametres to talk about the results of these studies. They are: learners, settings, tasks and planning.

Learner Variables:

1. Second and Foreign language learners 
2. Proficiency level of learners (most studies looked at intermediate level learners). Wigglesworth (1997), Kawauchi (2005) and Tavakoli and Skehan (2005) manipulated proficiency as a variable. 
3. Learner's orientation to planning 
4. Individual learner difference factors

Settings Variables:

1. Classroom
2. Laboratory
3. Testing

These variables are connected to length of planning time. Compared to testing context, the other two settings provided longer planning time to learners. 

Task Variables:

1. Interactive Variables (Monologic vs. Dialogic tasks)
2. Task Complexity (Simple vs. Complex tasks)

All the testing studies included in Ellis' list used monologic tasks in order to control the multitude of influences that come in with an interlocutor. All initial testing studies used monologues. But there are dialogic testing studies available. 

Task complexity or task difficulty is a difficult topic due to many variables involved in it. The factors affecting complexity, and used in the studies listed here are: degree of familiarity with the task context, the degree of structure in the information to be communicated, the number of distinct referents to be encoded and temporal reference (Here-and-Now vs. There-and-Then).

Planning:

1. Length of planning time
2. Guided vs. Unguided planning
3. Form-focus vs. Meaning-focus

Most teaching research used ten minute planning time. Testing research uses lesser duration. Wigglesworth (1997) used 1 minute, Elder and Iwashita (2005) used 3 minutes, and Tavakoli and Skehan (2005) used 5 minutes. Mehnert (1998) studied the effect of varied planning times and found that longer planning time had more effect on performance. 

Guided planning asks learners to do particular things while planning, while unguided condition doesn't. Kawauchi (2005) studied three kinds of guided planning: writing what was planned, rehearsal of what is to say, and read a model of what to say. 

How does the above variables affect Fluency, Complexity and Accuracy?

Fluency

Operationalisation of Fluency: a. Measure of temporal aspects of fluency (number of words/syllables per minute), b. measure of repair phenomena (false starts, repetitions, reformulations). 

General finding in teaching studies is that strategic planning has a positive effect on fluency in both temporal and repair fluency aspects. But in testing, this is different. Elder and Iwashita (2005) found no effect, and Wigglesworth (2001) found negative effect. 

Second and foreign language learners experienced positive effects of planning on fluency.

Influence of proficiency level on the effect of planning on fluency was found to be varied. Wigglesworth (1997) found greater effects on the fluency of high proficiency test-takers. Kawauchi (2005) reports positive effect on low and high proficiency learners, but not on advanced learners (probably because they did not need planning time to speak well). Tavakoli and Skehan found that high proficient learners performed better than low proficient learners. Thus with the available data, no conclusion can be made on the effect of planning time for learners of different proficiency levels.

Learner's attitude towards the opportunity to plan found varied results in different studies. 

Learner's Memory played a role in fluency in some studies. Guara-Taveres (2008) found that learner's working memory and measures of fluency correlated well when planning time was available. 

Effect of Settings have clear conclusions. In laboratory and classroom settings, planning time has positive effects on performance. But in testing context, it seems to have lesser or no effect. 

With the available studies, one cannot make a conclusion regarding fluency about the participatory structure of tasks. Majority of studies involving dialogic tasks showed positive effect. Only two studies in monologic tasks did not show an effect. 

Task complexity was well studied in Foster and Skehan's studies. They used personal information, narrative and decision making tasks. The first was deemed easy because no external information was needed. The third was deemed more difficult because of the unfamiliarity of information to be communicated, and its lack of availability of structure. Mehnert (1998) found more effect on fluency in more structured tasks. Tavakoli and Skehan (2005) found more effect on fluency on structured tasks. In short, planning interacts with task complexity/difficulty, and the effect on fluency is more in case of less complex tasks. 

Length of Planning seems to have a clear effect on fluency. Mehnert (1998) found that longer the planning time, greater the effect. 

Type of Planning has an effect. Guided planning had more effect on fluency than unguided planning. But more studies are needed to find when guided planning works better than unguided planning- whether it depends on the nature of the task, proficiency of learners, etc.

Complexity

Operationalisation or measurement of complexity was done through: a. amount of subordination, number of different verb forms used, type-token ration and number of different word types. Results are more mixed than those of fluency studies, although there is plenty of evidence that strategic planning helps up complexity of production. 13 of the 19 studies reported here showed positive effects, while the rest (6) did not find any effect. Overall, strategic planning appears to have a greater effect on grammatical complexity. 

Both second and foreign language learners recorded benefit from planning on complexity. 

Proficiency: Advanced learners may not benefit from planning in terms of complexity (Kawauchi, 2005).

Working memory was found to be significantly related to complexity in planning group, not in no-planning group (Guara´-Tavares, 2008).

Complexity doesn't depend on laboratory/class setting. In testing, there is very less or no effect on complexity.

Task factors interact with planning time to have an effect on complexity, but 'how' is not clear. Most dialogic and monologic tasks showed a positive effect of planning on complexity. 

Task complexity: Foster and Skehan (1996) found that more complex decision making tasks did not have an effect on complexity while personal information and narrative tasks have higher grammatical richness with planning condition. But other studies give different results. More studies are needed to reach conclusions. 

Planning time variable: Mehnert's (1998) is the only study in planning time variable reported no effect on complexity in all of her different conditions. Different types of planning also did not have any effect on complexity. The degree of guidance might have an effect on the outcomes, however. 

Accuracy 

Accuracy also showed mixed results in various results. Thirteen of the studies found that planning enhanced accuracy but six reported no effect. 

Learner’s proficiency has an effect on accuracy. Kawauchi (2005) found less effect on advanced level learners than low proficiency learners. Learner proficiency needs to be controlled while investigating effects of planning on accuracy. 

Learners’ attitudes towards planning also have an effect on accuracy. 

Working memory wasn't found to be related to accuracy.

Task type is a potential influence factor. Interaction between task type and planning where accuracy is concerned. Foster and Skehan (1996) reported that planning led to greater accuracy in personal and decision making tasks (low and high difficulty tasks). No conclusion is really possible about how task type influences the effect that planning has on accuracy. How learners orientate to the task is also an important task. 

Type of planning failed to find effects in the studies listed here. Mochizuki, N. and L. Ortega. (2008) showed that when the guided planning is focused it can have an effect on accuracy. 

General Comments

Overall, strategic planning has clear effects on task performance. In the light of research, it is possible to say that conclusions about learner and task variables' influence on performance can be made. But we need more data and more studies that carefully control and manipulate these variables. 

Ellis questions: The three dimensions of performance we chose are not perfect descriptors of performance. Are ratings based on these these dimensions sensitive to the influence of strategic planning? This doubt is natural since no study reported an effect of planning on the ratings even when there were differences in discourse analysis results! It may thus seem that ratings are sensitive to influence of strategic planning on fluency in learning context, not in testing. 

Thus testing context seems insulated to the influence of strategic planning in terms of fluency. Only Wigglesworth (1997) showed that there is a significant effect (in discourse analysis). Why such insulation? Ellis speculates that it is because the test-taker knows that he/she is being tested, which leads to focus on accuracy at the expense of fluency and complexity. That is, testing context neutralizes the influence of planning otherwise available in learning contexts. Or may be the length of planning must be longer (althouth Mehnert (1998) proves this wrong). 

But in learning studies, strategic planning is found to have consistent influence on fluency throughout almost all studies. Prior planning of what to say saves on attentional resources enabling learner to speak fluently. Skehan proposes this trade-off between aspects of performance when learners focus on one aspect of performance. Depending on what is prioritized, the other aspects suffer. This explains the variable results of many studies. More studies are needed to say definite things about the influence of learner characteristics and task characteristics. 

Proficiency is one such variable that must be studied. Except in testing context, it has shown variations. 

Task variables like degree of structure need to be studied in detail. Existing studies have shown effects. But what is less clear is how task structure interacts with planning. 

Other considerations are: 

• Whether planning is guided or unguided.
• Whether focus is invited to form or meaning.

3. Studies in Within-task planning time

In fact there is only few studies that report this. Yuan and Ellis (2003) compared the performance of learners in pressurised (no planning) and unpressurised (within-task planning) planning time conditions. Learners with the within-task planning condition spoke longer. Fluency was not significantly different for both groups. Within-task planning resulted in greater syntactical complexity (without much differences in syntactical and lexical variety). It also generated more accurate speech in terms of error-free clauses and verbs. Surprisingly, there was no effect on fluency, probably due to the pressure to speak without prior planning. Thus the study concludes that when given ample time to plan, we can expect more accurate and complex speech in learning contexts. 

One problem with this kind of planning is that we do not know what the learners were doing during the planning stage. Other studies have shown that the effect of unpressurised planning is most beneficial in the initial stages of the task performance. 

The summary of another study by Ahmadian and Tavakoli (2010) can be accessed at this link. (Language Teaching Research, Vol. 15, Issue 1). 

Summary

Strategic planning is the most researched planning type so far. This preference is not theory-based. The other two types of planning must be examined with equal vigour. 

Rehearsal results in greater fluency and complexity. But these effects do not transfer to the performance of a new task unless there is some kind of additional intervention. That is, simple repetition of a task may not have a measurable impact on acquisition.

Strategic planning clearly benefits fluency. Results are mixed with complexity and accuracy. The possible trade-off between these two aspects must be the reason (i.e. learners will tend to prioritize either complexity or accuracy). Other variables which have an impact on the effect of strategic planning are the learners’proficiency (the effects are less evident in very advanced learners),the degree of structure of the information in the task and working memory. 

Within-task planning may benefit complexity and accuracy without having a detrimental effect on fluency.

Theoretical Perspectives

Theories of variability

Levelt's model of speaking

Skehan's theory

Robinson's theory

Levelt's Model 

There are three overlapping processes: conceptualisation, forumlation and articulation. The utterances can be monitored prior to and after the production. 

Two characteristics of speech production: a) controlled and automatic processing, b) incremental production. Conceptualiser and monitor operate under controlled processing. Formulator and articulator operate under automated conditions. However, the cases of native speakers and learners might be different in terms of formulation and articulation. 

Putting Levelt's model along with the limited attentional processes of learners explains many findings of the studies discussed above. The relationships between planning and aspects of performances can be understood with this theoretical background. 

• Rehearsal and strategic planning are likely to assist conceptualization and thus facilitate fluency
• They may have effects on formulation and articulation as well since the linguistic resources necessary are already accessed during conceptualisation. 
• Fluency oriented learners may not benefit in terms of complexity and accuracy. In other words, since only limited resources are available, focus on one aspects leads to problems in other aspects of performance. 
• Advanced learners who have lesser problems in formulation and articulation will have an effect on fluency, but much less on complexity and accuracy. 
• In unpressurised within-task planning, complexity and accuracy may increase due to benefits to formulation. 

These accounts are helpful in understanding how things work. But we also need to know how individual differences interact with different aspects of performance and variables we study. All learners do not engage in all the processes to the same extent. Orientation, working memory, language aptitude, willingness to communicate, and anxiety are a few such individual differences. 

A framework suggested by Ellis has four sets of variables. 

TTT

The model hypothesises that task and individual variables influence how learners plan and mediate the effect planning has on production. We need to answer the question 'how does planning assist development of fluency and acquisition of linguistic knowledge'. This has yet to be studied. Fluency development and acquisition must be two different phenomena. Like Skehan says, may be fluency is an outcome of development of exemplar-based system. So fluency can develop independent of acquisition. Rehearsal and strategic planning helps learners to develop exemplar-based system. Therefore, such planning helps build fluency. Within-task planning might influence automatization of grammatical knowledge. 

There are three senses of acquisition: a) acquisition of new linguistic features, b) restructuring of existing linguistic resources and c) development of greater control or accuracy over existing linguistic features. This understanding is necessary to theorize the relationship between planning and acquisition. The studies have showed that planning has very less influence on first kind of acquisition. Second and third kind of acquisition experiences effects of planning. Planning affects restructuring by its effect on complexity (Skehan, 1998). These assumptions are based on the condition that more complex production leads to acquisition. 

Limitations and Directions for Future Research

There is lack of information on what learners do during planning. 

Within-task planning and the combined effects of within-task and pre-task planning haven't been studied yet. 

Longitudinal study of the effects of planning has not been done yet. The maximum duration so far is ten weeks!

Studies listed did not collect baseline data of native speakers performing the same tasks. 

Stuidies did not give proficiency level data of the learners. 

No study has investigated the extended performance of learners on a task (not just the early stage of the task, but the entirety of the task performance). 

How individual learner factors affect performance is not studied yet.

References

Bygate, M. (1996). ‘Effects of task repetition: Appraising the developing language of learners’ in J. Willis and D. Willis (eds): Challenge and Change in Language Teaching. Heinemann.

Bygate, M. (2001). ‘Effects of task repetition on the structure and control of oral language’ in M. Bygate, P. Skehan, and M. Swain (eds): Researching Pedagogic Tasks, Second Language Learning, Teaching and Testing. Longman.

Elder, C. and N. Iwashita. (2005). ‘Planning for test performance: Does it make a difference?’ in R. Ellis (ed.): Planning and Task Performance in a Second Language. John Benjamins.

Ellis, R. (2005). ‘Planning and task-based research: theory and research’ in R. Ellis (ed.): Planning and Task-Performance in a Second Language. John Benjamins.

Foster, P. and P. Skehan. (1996). ‘The influence of planning on performance in task-based learning,’ Studies in Second Language Acquisition 18/3: 299–324.

Gass, S., A. Mackey, M. Fernandez and M. Alvarez-Torres. (1999). ‘The effects of task repetition on linguistic output,’ Language Learning 49: 549–80.

Kawauchi, C. (2005). ‘The effects of strategic planning on the oral narratives of learners with low and high intermediate proficiency’ in R. Ellis (ed.): Planning and Task-Performance in a Second Language. John Benjamins.

Mehnert, U. (1998). ‘The effects of different lengths of time for planning on second language performance,’ Studies in Second Language Acquisition 20: 52–83.

Mochizuki, N. and L. Ortega. (2008). ‘Balancing communication and grammar in beginninglevel foreign language classrooms: A study of guided planning and relativization,’ Language Teaching Research 12: 11–37.

Sheppard, C. 2006. The Effects of Instruction Directed at the Gaps Second Language Learners Noticed in their Oral Production. Unpublished PhD Thesis, University of Auckland.

Skehan, P. (1998). A Cognitive Approach to Language Learning. Oxford: Oxford University Press.

Skehan, P. and P. Foster. (1999). ‘The influence of task structure and processing conditions on narrative retellings,’ Language Learning 49/1:93–120.  

Tavakoli, P. and S. Skehan. (2005). ‘Strategic planning, task structure, and performance testing’ in R. Ellis (ed.): Planning and TaskPerformance in a Second Language. John Benjamins.

Wigglesworth, G. (1997). ‘An investigation of planning time and proficiency level on oral test discourse,’ Language Testing 14/1: 21–44.

Yuan, F. and R. Ellis. (2003). ‘The effects of pre-task and on-line planning on fluency,complexity and accuracy in L2 monologic oral production,’Applied Linguistics 24/1: 1–27.