Dr. Rod Ellis: TESOL Written Corrective Feedback

Professor Rod Ellis, gave a presentation which is available on YouTube.com. In it, he focuses on written corrective feedback. I’ve written a basic summary below. Get a drink, a snack, your notebook, make yourself comfortable and enjoy an allusive, informative explanation of the current state of affairs regarding written corrective feedback; the types and strategies, what we know, what we don’t know and what we should do.

[jwplayer file=”http://www.youtube.com/watch?v=wn35iHCljC8″]

Running time: 1:09:08

Why do we give written corrective feedback?

  1. To enable learners to revise their own writing, i.e. produce a better second draft
  2. To assist learner to acquire correct English

A Typology of corrective feedback types

  1. Strategies for providing corrective feedback
  2. How learners respond to the feedback

Written corrective feedback strategies

1. Direct written corrective feedback

Teachers provide correct form, i.e. crossing out an unnecessary word, phrase or morpheme, inserting a missing word, phrase or morpheme, inserting a missing word or morpheme, and writing the correct form above or near to the erroneous form (Ferris 2006)

  • Advantage – Provides learners with explicit guidance about how to correct their errors. Ferris and Roberts (2001) suggest direct written corrective feedback is probably better than indirect written corrective feedback with writers of low levels of language proficiency.
  • Disadvantage – It requires minimal processing on the part of the learner and thus, although it might help them to produce the correct form when they revise their writing, it may not contribute to long-term learning.

However, a recent study by Sheen (2007)* suggests that direct written corrective feedback can be effective in promoting acquisition of specific grammatical features (Low intermediate level learners).

* The effect of focused written corrective feedback and language aptitude on ESL learners.

2. Indirect written corrective feedback

Involves indicating that the learner has made an error but without actually correcting it. This can be done by underlining the errors or using cursors to show omissions in the learners’ text or by placing a cross in the margin next to the line containing the error. In effect, this involves deciding whether or not to show the precise location of the error, i.e. just indicate which line of text the error is on.


  • Caters to ‘guided learning and problem solving’ (Lalande 1982) and encourages learners to reflect on linguistic forms
  • Considered more likely to lead to long-term learning (Ferris and Roberts 2002)


  • Learners cannot correct if they do not know the correct form
  • Learners may be able to correct but will not be certain that they are correct

The results of studies that have investigated direct vs. indirect written corrective feedback are very mixed (cf. Lalande 1982 and Ferris and Robert’s 2002). No study to date (2012) has compared the effects on accuracy in new pieces of writing.

3. Metalinguistic written corrective feedback

Provides learners with some form of explicit comment about the nature of the errors they have made.

  • Use of error codes, i.e. abbreviated labels for different kinds of errors placed over the location of the error in the text or in the margin. e.g. art = article, prep = preposition, sp = spelling, ww = wrong word, t = tense, etc.
  • Metalinguistic explanations of their errors, e.g. numbering errors and providing metalinguistic comments at the end of the text.

Informal poll: learners were in favour of metalinguistic explanations but teachers were not. Rod Ellis suggested that it had something to do with hard work on the teachers’ part.

Studies on use of metalinguistic error codes

  • Lalande (1982) – A group of learners of L2 German that received correction using error codes improved in accuracy in subsequent writing whereas a group receiving direct correction made more errors. However, the difference between them was not statistically significant.
  • Robb at al (1986) – The use of error codes no more effective that three other types of written corrective feedback they investigated, i.e. direct feedback and two kinds of indirect feedback.
  • Ferris (2006) – Error codes helped learners to improve their accuracy over time in only two of the four categories of error she investigated, i.e. in total errors and verb errors but not in noun errors, article errors, lexical errors or sentence errors (e.g. word order errors).
  • Ferris and Roberts (2001) – Error codes helped learners to self-edit their writing but no more so than indirect feedback.

Overall then, there is very limited evidence to show that error codes help writers to achieve greater accuracy over time and it would also seem that they are no more effective than other types of written corrective feedback in assisting self-editing.

Studies on use of metalinguistic error explanations

This is less common than error codes. It’s time-consuming and calls for the teacher to be able to write clear and accurate explanations for a variety of errors.

Sheen (2007) compared direct and indirect metalinguistic written corrective feedback. Both were effective in increasing accuracy in the learners’ use of articles in subsequent writing completed immediately after the written corrective feedback treatment but the metalinguistic written corrective feedback proved more effective that the direct written corrective feedback in the long term, i.e. in a new piece of writing completed two weeks after the treatment.

Rod Ellis speculated that metalinguistic written corrective feedback forces learners to formulate some kind of rule about the particular grammatical feature and then they use this rule but it takes time for them to be able to use this rule effectively. Direct feedback might have an immediate effect but learners soon forget the correction, whereas if they’ve learned the rule, maybe it’s going to have a longer term effect on learners’ ability to avoid the errors.

4. Focus of the feedback

Focused vs. unfocused written corrective feedback

1. Focused written corrective feedback advantages, i.e. correcting just one type of error

  • provides multiple corrections of the same error
  • is more likely to be attended to by learners
  • is more likely to help learners to develop understanding of the nature of the error

2. Unfocused written corrective feedback advantage, i.e. correcting all or most of the errors

  • addresses a range of errors, so while it might not be as effective in assisting learners to acquire specific features as focused written corrective feedback in the short term, it may prove superior in the long term.

The distinction of focused and unfocused written corrective feedback applies to all of the previously discussed options. The bulk of written corrective feedback studies completed to date have investigated unfocused written corrective feedback. Sheen (2007) – Focused written corrective feedback, i.e. errors in the use of articles for the first and second mention, proved effective in promoting more accurate language use of this feature. However, to date (2012), there have been no studies comparing the relative effects of focused and unfocused written corrective feedback.

5. Electronic written corrective feedback

Extensive corpora of written English can be exploited to provide learners with assistance in their writing. Electronic resources provide learners with the means where they can appropriate the usage of more experienced writers.

An example of electronic written corrective feedback

“Mark My Words” (Milton 2006)

  1. An electronic store of approximately 100 recurrent lexico-grammatical and style errors that he found occurred frequently in the writing of Chinese learners
  2. A brief comment on each error an with links to resources showing the correct form
  3. Teachers use the electronic store to insert brief metalinguistic comments into learners’ text
  4. Learners consult the electronic resources to compare their usage with that illustrated in the samples of language made available. This assists learners to self-correct.
  5. An error log for each piece of writing, drawing learners’ attention to recurrent linguistic problems is generated

There has been no research to investigate whether this is effective or to investigate whether it has any actual effect on language acquisition, as measured in new pieces of writing.


  • Removes the need for the teacher to be the arbiter of what constitutes a correct form. Teachers’ intuitions about grammatical correctness are often fallible; arguably a usage-based approach is more reliable
  • Allows learners to locate the corrections that are most appropriate for their own textual intentions and encourages learner independence

6. Reformulation written corrective feedback

This involves native-speakers rewriting learners’ texts in such a way as ‘to preserve as many of the writers’ ideas as possible, while expressing them in their own words so as to make the pieces sound native-like’ (Cohen 1989: 4) The writers then revise their writing by deciding which of the native-speakers’ reconstructions to accept. In essence then, reformulation involves two options ‘direct correction’ + ‘revision’ but it differs from how these options are typically executed in the whole of the learners’ texts are reformulated thus laying the burden on learners to identify the specific changes that have been made.

Sachs and Polio’s (2007) study

  • This study compared reformulation and direct correction.
  • Learners were shown their reformulated/corrected stories and asked to study them for 20 minutes and take notes if they wanted.
  • One day later, they were given a clean sheet of paper and asked to revise their stories but without access to either the reformulated/corrected texts or the notes they had taken.
  • Both the reformulation and direct correction groups outperformed a control group. However, the correction group produced more accurate revisions than the reformulation group.
  • It should be noted, however, that reformulation serves also to draw learners’ attention to higher order stylistic and organisational errors.

Types of learner response

  1. Revision required
  2. No revisions required
    • Learners asked to study corrections
    • Learners just given back corrected text

Rod Ellis notes that learners may only look at their grade and nothing more if they aren’t required to study their corrected texts.

Ferris (2006) study

Ferris (2006) identified a number of revision categories in the re-drafts of 146 ESL learners’ essays. Out of the corrected errors:

  • 80.4% were eliminated in the redrafted compositions either by correcting the error or by deleting the text containing the error or by making a correct substitution.
  • 9.9% of the errors were incorrectly revised
  • 9.9% no change was made

Overall, research shows that written corrective feedback assists revision. Ferris’ descriptors were as follows:

Label Description
Error corrected Error corrected per teacher’s marking.
Incorrect change Change was made but incorrect.
No change No response to the correction was apparent.
Deleted text Student deleted marked text rather than attempting correction.
Substitution, correct Student invented a correction that was not suggested by the teacher’s marking.
Substitution, incorrect Student incorrectly made a change that was not suggested by the teacher’s marking.
Teacher-induced error Incomplete or misleading teacher marking caused by student error.
Averted erroneous teacher marking Student corrected error despite incomplete or erroneous teacher marking.

An important theoretical issue

Theories of language learning differ in the importance they attach to:

  • Noticing the feedback in input
  • Revising the correct linguistic forms in output

But no research has addressed this issue.

Chandlers’ (2002) study

This compared indirect written corrective feedback plus the opportunity to revise with indirect written corrective feedback with no opportunity to revise. Results:

  • Accuracy improved from the first to the fifth piece of writing significantly more in the group that was required to correct their errors than in the group that just received indication of their errors
  • This increase in accuracy was not accompanied by any decrease in fluency

However, this study cannot be used to claim that written corrective feedback with revision contributes to L2 learning as there was no control group, i.e. a group that received no written corrective feedback. Rod Ellis notes that a great weakness of studies that have investigated written corrective feedback is that the studies have had no control groups and this makes it very difficult to say whether the written corrective feedback is actually having any effect on learning.


The situated nature of written corrective feedback

Hyland and Hyland (2006) commented, ‘it may be … that what is effective feedback for one student in one setting is less so in another’ (p.88).
A sociocultural perspective on written corrective feedback would emphasise the need to adjust the type of written corrective feedback offered to learners to suit their stage of development (Aljaafreh and Lantolf 1994) although how this can be achieved practically remains unclear in the case of written corrective feedback.

By teachers

Teachers need to consider the various options and formulate an explicit policy for correcting errors in learners’ written work. They also need to subject their policy to evaluation by evaluating the effects of their error correction, e.g. through action research.

By researchers

There is an obvious need for carefully designed studies to further investigate the effects of written corrective feedback in general and of different types of written corrective feedback. Guenette (2007) observed that is is important that studies are conducted in a way that make them comparable but sadly that has not typically been the case. A typology of written corrective feedback provides a classification of one of the key variables in written corrective feedback studies – the type of written corrective feedback – which can serve as a basis for research.

Are Flash and HTML5 locked in a mortal struggle for control of the internet?

Are Flash and HTML5 locked in a mortal struggle for control of the internet?

It’s a loaded question, isn’t it? The kind of attention grabbing headline we’ve come to expect from the mainstream media who receive a substantial portion of the $691,000,000 (2010) of Apple Inc.’s annual marketing budget. So what of this epic struggle between Adobe’s flagship software platform and the open source, open standard HTML5?

Some sobering facts

  • HTML was born* in 1995.
  • Javascript was also born in 1995.
  • CSS was born in 1996.
  • Flash was born in 1997.

* By “born” I mean the first working versions of the respective languages and runtimes were released to the public, i.e. HTML 2.0 and Flash Player 2.0.

So none of them are new and they all get significant new features added to them from time to time. HTML, CSS, Javascript and Flash have co-existed, collaborated and integrated with each other for the past 14 or so years. They’ve done very well together and if we took any one of them away, the WWW would be a poorer place for it. They all have their merits:

  • HTML is open specification and great for flexibility and accessibility. HTML text flows naturally across the screen, browsers can apply anti-aliasing to make it smoother on the eye, the text can be resized (Ctrl + mouse wheel) which is perfect for the sight-impaired, assistive technologies can convert the text to speech for accessibility, etc. In short HTML is wonderful for everyone.
  • CSS (Cascading Style Sheet) defines the physical appearance (look and formatting) of web pages, for example defining text fonts, sizes, colours and styles, the arrangement of areas of text, images and other elements on the page.
  • Javascript is a flexible, open format, object oriented scripting language that runs natively in web browsers. It adds interactivity to web pages transforming static, inert HTML elements into interactive objects that respond to users’ actions. Since 2000, Javascript has also been commonly used in elearning SCOs, e.g. Adobe Captivate, Articulate and Raptivity, to relay data from Flash applications to Learning Management Systems’ SCORM modules. It’s now becoming more widespread with the introduction of code libraries such as JQuery and MooTools which make programming with Javascript’s idiosyncrasies much easier.
  • Flash and its native programming language, Actionscript, provide the whiz-bang wow factor on the WWW. Its role has always been to do the things that web developers couldn’t and can’t currently do on the WWW with HTML, CSS and Javascript alone or where it is impractical to do so. Its primary rise to internet fame was in providing a platform to display scaleable vector graphics (SVG) and animation in web browsers, i.e. images that move and don’t get pixelated when you expand or zoom them. Shortly after that it provided support for sound and then video. Before Flash Player supported video, it was possible to play video on web pages with other plugins like Apple Quicktime, Windows Media Player and Real Networks Real Player. However, they all used different, proprietary video formats that weren’t cross-compatible (See Youtube API Blog link below). Flash Player is currently the only way to do web conferencing with access to webcam and microphone in a browser. The most recent version of Flash Player (11) introduces 3D graphics engines and GPU hardware acceleration: http://away3d.com/

In short, they’ve all had a long and productive history together and they’ve all contributed to making the web a richer, more enaging, more accessible medium. At one time or another, they’ve all had their critics and predictions of their demise. Will HTML5 kill Flash? More likely, HTML5 will gradually replace HTML4 and some but not all of what Flash currently does. No killers, no victims and not very sensational after all.

Further reading

Media Player module now supports HTML5 video

Media Player module now supports HTML5 videoThere has been a lot of debate about Flash and HTML5 video ever since Apple and Steve Jobs took the decision to block Flash from their iOS operating system. Currently, iPhone and iPad users can’t view video or audio deployed on Moodle. Now the Media Player module for Moodle brings support for HTML5 video tags to resolve this issue.

What’s the Media Player module?

It’s a Flash based activity module for Moodle 1.8 and 1.9 that plays a wide range of media formats without the need for any special programming skills. Flash has been the de facto method for deploying audio and video on the web for at least the last ten years. Everyone uses it because it’s more stable, less intrusive and works in more browsers and on more operating systems than any other method. Basically, if you want the maximum number of users to be able to view your video content, Flash is the best choice.

Not only does it guarantee the best compatibility available, it also has all the other advantages and advanced features of Flash. At the heart of the Media Player module is a stable, powerful and feature rich Flash based media player. It can play a wide variety of video formats and play video streamed from a media servers (RTMP) including live feeds and can switch between high and low definition video streams according to users’ available bandwidth. It supports a variety of playlists, Flash animations, audio, thumbnails and poster images, external caption files, external audio tracks, animated and/or interactive overlays and full-screen display mode. This is what sets the Media Player module apart from other methods of deploying media.

Why include support for HTML5?

A short while ago, Apple Inc. took the decision to block Flash from all their iOS mobile devices including iPhone, iPod and iPad. This means that Apple iOS users can’t view video on the majority of websites. Unfortunately, this also means that learners who have Apple iOS devices can’t view video or listen to audio deployed on Moodle. Subsequently, I have received a lot of requests for the Media Player module to support HTML5 video. Initially, because I designed the module as an advanced, interactive activity module for video, I didn’t think it was appropriate to support HTML5 video. However, on reflection, I’ve realised that the Media Player module is now the only viable way for non-developers to deploy video in Moodle to accommodate learners who have Apple iOS devices.

What can we expect from HTML5 video?

HTML5 video is a simple and quick way to deploy simple web video on browsers that support it. These currently include MS Internet Explorer 9 (but not IE7 or IE8), Apple Safari, Opera, Google Chrome and Firefox. However, HTML5 is not Flash and so we can’t expect the same advanced features. HTML5 supports RTMP streaming in theory but it’s dependent on users’ web browsers supporting it which, at the moment, most don’t. That brings me to two main caveats of using browser based video playback.

For one;  it’s dependent on browser support and how the web browser interprets the HTML5 scripting. Different web browsers interpret the same HTML, HTML5 and Javascript code so that it can appear and behave differently.

The other; there’s currently a conflict between some powerful interested parties about which video CODEC to use. Firefox is pushing for the open source Ogg, while Google would like WebM and Apple and Microsoft would like to push H.264. Currently, this means that if you want to deploy video across all the main browsers using HTML5, you have to provide at least 3 versions of each video file: One as Ogg, one as WebM and one as H.264, tripling the required storage space for video on your servers. Luckily, it’s only Apple iOS that blocks Flash and Flash supports H.264, so if you deploy videos with Flash with H.264 and provide an HTML5 fall-back, you only need to provide one video file so you’ll get fully functioning interactive Flash video on all other desktops, laptops and mobile devices, and simple HTML5 video on Apple iOS devices; iPhone, iPod and iPad.

And in the future?

Hopefully, the conflict between Firefox, Google, Apple and Microsoft for a video CODEC standard can be resolved and web browser developers can move towards more standardised interpretation and support of HTML5 video. There are also several projects under way for providing more feature rich video experiences and I expect that deploying web video without Flash will get easier.

Further reading about HTML5 video: http://en.wikipedia.org/wiki/HTML5_video

Media Player module for Moodle project site on Google Code: http://code.google.com/p/moodle-mplayer/

New Media Player module for Moodle

In this article, I’m going to give you an introduction to the new Media Player module for Moodle. It’s a flexible, robust and feature-rich method of deploying video in Moodle as an activity.

The Media Player module for Moodle using Searchbar and Playlist features

In November 2009, I started the FLV Player module for Moodle project. It was a way of deploying video in Moodle that was robust, standards compliant and above all easy to use for non-developers. It’s been a great success and I’ve have a lot of feedback from teachers, course content developers and admins. As a result of this, I’ve decided to update the module and include a number of new features. I’ve developed this new version as a separate and distinct module to avoid teachers and course content developers having to redeploy existing instances of the FLV Player module due to conflicts between the old and some of the new module’s settings.

You can already deploy video in Moodle. Why create a Module for it?

Moodle already has media filters that automatically convert HTML links to video files into instances of video player plugins, including Flash, QuickTime, RealPlayer and Windows Media Video. These work well for basic video deployment but don’t allow users to:

  • Decide which video player plugin to use
  • Control how the video player looks and behaves
  • Allow you to deploy streaming video from a media server
  • Do anything other than basic video playback functions

The Media Player module uses a single, extremely well developed and supported Flash video player (JW FLV Player) which effortlessly and gracefully handles the majority of web video formats, including FLV and F4V (Flash video), M4V and MOV (Quicktime) and MP4. It also supports the new and popular H.264 (Blu-ray) video CODEC and of course the most asked for feature in web video players, a variety of playlist formats.

Also, the only way to deploy captions with video is to hard-code them into the video file which is inflexible, doesn’t adjust when the video is scaled and doesn’t support multiple languages. External captions, on the other hand, are very flexible, easy to edit and easy to read at any magnification.

Obviously, many teachers and course content designers would like to do much more than basic video playback deployment for e-learning purposes and that’s where the Media Player module comes in.

But video is a resource. Why is Media Player an activity module?

If you only deploy video and nothing more, then it isn’t interactive and it would be unreasonable to call it an activity. The Media Player module includes options that have quite a high degree of interactivity such as Snapshot and Searchbar. As you’ll see while you read this article and try out the demos, it’s much more than a video player and will continue to support more features as they become available.

So what can I do with the Media Player module?

There’s a lot you can do with it and you can also use all of these features in combination with each other. The features are difficult to describe and I think it’s much better to see them demonstrated. See the links at the end of this article for some demos.

Here’s a list of the available options:

  • External captions files: Supporting the popular SMIL and SubRip captions standards which allow very detailed control over how captions are displayed. You can also deploy the same video multiple times with different captions that play in the same playlist. Learners can immediately see what captions are available and there is no screen refresh when they select different ones. The captions can also be turned on or off at any time during playback.
  • High and normal definition video files: You can deploy two versions of the same video, one normal definition and the other HD. Users can switch between the videos according to the speed of their Internet connection. If you use a streaming media server, you can also use automatic bandwidth checking so that the video player automatically finds the optimum definition of video to play.
  • Info box: A consistent way to display information about the video being played (title, description, author and date deployed). An easy way to comply with copyright and licensing requirements.
  • Livestream: This one if for live video broadcasts from media servers. Normally, users have to keep checking manually and refresh the web page every few seconds to see if a live broadcast has started. This feature automatically checks at defined intervals to see if the broadcast has begun without refreshing the web page and then plays the video so users are free to do other things while they’re waiting.
  • Logobox: Include a logo with videos and also a link. It also supports Flash animation files so you can have an animated logo. The link could be to a web page or to a downloadable ZIP file.
  • Metaviewer: Displays metadata information of the video files being played. It’s a convenient way for teachers and course content developers to find out essential information about the video file such as the exact width, height and duration.
  • Playlists: By far the most asked for feature on video players is the ability to deploy several videos in one player. For example, if you have a video which is very long, it’s necessary to split it up into shorter (5 – 10 minute) sections or chapters and deploy them in order in one presentation. It supports thumbnail images, titles and descriptions for each item on the playlist. This means that users can easily return to a video and carry on watching from more or less where they left it. It’s also much easier to find a particular section without having to download the entire video. It supports several standard playlist formats including those produced by YouTube.com and iTunes.
  • Search bar: Allows users to perform keyword searches on sites such as YouTube.com or, if you have a custom search script, anywhere you wish to define. It’s useful if you’d like users to do research without leaving your site.
  • Snapshot: Allows users to take snapshots of frames of the video being played. The snapshots are stored in the course files directory and a link returned to the user. They could use this to post snapshots in course forums or blogs. The ability to store snapshots is controlled by creating a special directory in the Moodle course files directory for each user. To protect your server and users’ computers, the Snapshot feature follows the Flash Player security model and only allows users to take snapshots of videos hosted on the same site as the Moodle. It’s possible to enable other sites but only with a correctly configured crossdomain.xml policy file.
  • Use YouTube.com as a video hosting service: Play videos directly from YouTube.com without any annoying advertising or popups and without users accidentally “clicking through” to the YouTube.com site. Only a small unintrusive YouTube.com logo appears in the bottom right of the screen. A cost-effective solution if you don’t mind making your video content publicly available and has the additional benefit of promoting your e-learning courses to a huge audience.

How can I start using it?

The Media Player module plugin for Moodle is open source and available to download and install from the project site hosted on Google Code. Please use the project Issues Tracker to report any problems or requests.

Can I see a demo?

There’s an HD (1280 x 720) video tutorial, deployed using the Media Player module, demonstrating how easy it is to deploy video with it here (login as a guest).

There are more demos of the various features on my Moodle here (login as a guest).