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Being critical: a practical guide

Evaluating information

Question everything...


Once you've found some interesting sources to use in your research, it's important that you evaluate each of them. This means deciding whether they're trustworthy, reliable and of good enough quality for an academic assignment.

In pretty much every aspect of our lives we are constantly making decisions: evaluating the pros and cons; the benefits, the drawbacks, and the possible outcomes... Whether it's shopping for clothes or searching for scholarly literature, listening to a friend's barely credible story, or watching the news, we're making evaluations about everything. The criteria you're judging by may even be pretty similar in all of those cases; just applied slightly differently.

So what criteria should we be looking at in terms of academic writing? The questions in the tabs below will help you to determine whether a source should be considered trustworthy or useful:

What should you look out for?

Who are the authors? Individuals? Experts? Companies?

Have they written other articles on the same topic?

Who published it?

Why is this important?

Reputation may help in determining trustworthiness. And it's not just the reputation of the authors or the publication. Can you find out if the work itself has been subsequently cited by anyone else?

What should you look out for?

What is the information?

Is it useful to your project?

Why is this important?

It needs to relate to your question – try to keep a focus on the question not just the general topic.

What should you look out for?

When was it published? Is it up-to-date?

Is it a significant milestone in the history of the topic?

Have the findings been superseded by later research?

Why is this important?

You're contributing to an ongoing discussion, so you want to reply to the latest points. Often you will need the most current information to answer your question. But don't just arbitrarily cut off anything over a certain age. It may still be relevant to consider significant older works.

What should you look out for?

Where did you find the information: website, blog, book, journal...?

Where was the research conducted?

Why is this important?

Always try to get your information from reputable sources. Mostly you'll be looking at scholarly sources like textbooks or peer-reviewed journals.

If you're looking at a website, what can you tell from its domain name (e.g. .ac, .gov, .uk)? Is there a date? And was the source of the link credible?

Pay attention to where the research took place, too. Research conduced in other countries may not always be relevant to the question you're trying to answer.

What should you look out for?

How was the research conducted?

Is it representative of other research in the field?

Is the evidence there, and has the argument been built up well?

How can you use it to answer your need?

Why is this important?

If it's a piece of research, how did they conduct it? Were the method and sample size appropriate and representative?

Will it support points you are making?

What should you look out for?

Why was it written?

What are the motivations behind it?

Why is this important?

Look out for bias and opinion pieces e.g. a pharmaceutical company publishing research that says their new drug is effective.

Breaking news! Following the evidence


To understand some of the principles by which we evaluate information, let's consider our reactions to a breaking news story:


You're on Twitter when you see:

Marjory's avatar

Marjory @MarjorySays1963 · 2m

OMG! Central Hall just literally took off and is now hovering over the lake!




A pretty wild claim. Whether you believe it or not will probably depend on whether you know Marjory and how much you trust what she has to say. But then you start to see other people tweeting about it.

Cat's avatar

Cat O'Logue @CatOLogue025_31 · 1m

Central Hall is flying! I'm stood outside Vanbrugh and the geese just went wild. Then there was a rumble and the whole of Central Hall just sort of came out of the ground.




Woofles's avatar

Prof. Woofles @Prof_Woofles · 1m

Um... central hall is flying dudes




Now the story has some corroboration, you can't help but begin to wonder if Central Hall is actually flying... But how could it be??

Marjory's avatar

Marjory @MarjorySays1963 · 42s

It's just sort of hanging there... #CentralHall

Central Hall flying over the lake, with Physics in the background.




Seeing is believing, but photos can be doctored. If only you could get a second opinion. Following the hashtag breaks you out of your own small group of follows and into the wider world of tweets being tweeted on the matter...

Pebble's avatar

Pebble Rah @BrightEyedPebble · 33s

I told you it was a spaceship! #CentralHall

Central Hall flying over the lake, with Vanbrugh in the background.




That's pretty much the same scene but seen from the opposite side of the lake. You can perhaps start to triangulate some sense of what's happening, or maybe start to find fault with the accounts being made. The more pictures come through, from more and more eye-witnesses, the more credibility the story will have.

If this were a real breaking news story, a news agency should be arriving on site soon. News agencies gather news stories to sell to newspapers and broadcasters. They have agents all around the world, and one of them is on their way to Heslington right now. It takes them about 20 minutes to get to the scene from York.

AYP's avatar

Associated York Press @AYP_BreakingNewsWire · 24s

WATCH LIVE: University of York #CentralHall hovers in the air.

Central Hall flying over the lake, with Physics in the background.




Soon everyone is tweeting about Central Hall, and all the news outlets are gearing up to cover the breaking story.





University of York building reported hovering over lake

 2 minutes ago

"Eye witnesses report..." starts the article: a fudge for "We can't yet corroborate this." The article is mostly made up of embedded tweets from said eye-witnesses, until such time as some proper journalists can get on site. When journalists start reporting, their reputation (and that of the organisation they represent) may lend even more credence to what's going on.

Radio and television are also reporting the breaking news. In terms of the BBC, this UK story will be breaking on Radio 5 Live. On television the BBC News channel will start broadcasting what scant pictures it has just as soon as it has them, but the radio doesn't have to worry about pictures and so can be a bit more flexible with how it fills its time. They may even be able to get an eye-witness or two on the phone.

But breaking news broadcasting is reactionary, and the quickest reactions are coming from those tweeting eye-witnesses on the scene with their cameras on their phones. If you're wanting the story as it happens, you're going to have to keep an eye on social media.

Then you see another tweet:

Eggy's avatar

Eggy Dave @Egg_123456789 · 11s

#CentralHall just fired some sort of energy weapon and is attacking the library! 😱

Central Hall hovering over the JBM, firing some sort of blue laser into it. There are flames coming from the library roof.




To be honest, it's hard to know what to believe anymore. Is Central Hall attacking the Library any more fanciful than it taking off and hovering over the lake? Still, nobody else seems to have got a photo of this event taking place. In fact it seems to be one of a number of joke tweets starting to emerge. Twitter loves a good meme to play with and riff upon, and this is just that. You're going to have to think even more critically about what you're seeing on twitter now the story has had time to trend.

But it's not just joke tweets you have to watch for. Other tweets may be looking to mislead with more sinister motives...

Derwent Rules!'s avatar

Derwent Rules! 💮🦆 @Derwent4Ever_63 · 9s

Police saying #CentralHall was stolen by #Langwith JCR who are still bitter about losing Hendrix Hall to #Derwent. Typical #Langwith dirty tricks! #DownWithLangwith #DerwentRules




Ah yes, the decades-old rivalry between Langwith and Derwent... Slurs and disinformation may be coming from both sides of this one. Campus security might eventually even feel the need to tweet to counter such claims. But by then who's listening? There's already loads of poisonous tweeting and retweeting blaming this college or that for what's happening to Central Hall. Some of the conspiracy theories emerging are downright baffling. And yet people seem to be believing them without question.

As the story develops, news outlets get in experts to offer their suggestions as to what might actually be going on. Evening news bulletins will be looking to provide a summary of the story, ideally with some on-the-scene reporting. Newspapers will be being sent to the press ready for the next morning.


University of York building suspended in air for several hours

Experts suspect cause was a buildup of gas from six decades of goose guano accumulating in University Lake


This is worse than that time with the Boomtown Rats

Abraham Lincoln in the style of a Guardian columnist

Abe Lincoln

So now we've got a story of record. It's published and out there. It's hopefully bringing in several first-hand accounts and 'triangulating' them to synthesize a better understanding of what took place. And it's hopefully bringing in expert analysis to try to pick apart what happened based on the available evidence.

Oh, and we've also got an opinion piece from a columnist. It gives us an idea of the columnist's own perspective on matters, which may or may not represent a broader perspective. It's one person's opinion, so we might treat what they have to say with caution.

Some newspapers might report the story more rigorously than others, too, or may approach the story from different socio-political perspectives...



Newspapers reflect the biases of their owners. Likewise online news platforms, and even television to some extent. We probably favour one outlet over another, because it is more in line with our own perspectives (just as we might follow people we like on social media and not follow people whose opinions we vehemently disagree with).But in doing that we still need to consider whether those innate biases might compromise our full understanding of a story. Again, we may need to consider more than one news source to 'triangulate' and build up a bigger picture of what took place.

Time passes, and the event, its causes, and its effects, may subsequently become a topic of scholarly interest. Researchers at the University might start to investigate the story in more detail, or even write about how it was covered on social media or in the national press. Be it the science at play, the societal impact, the historic ramifications, or some other element of what went on, there will be something about it somewhere that an academic may wish to draw upon in their research. That research will then be published in some form or another; perhaps as a journal article...

Journal of Building Propulsion : 24 (11) 1024-1111

The potential for goose-related gaseous levitations — lessons from the Central Hall incident at York

J.B. Morrell, H. Fairhurst, R. Burton

University of York, Heslington, York, YO10 5DD, UK

A lot of time has passed by this point. It can no longer be said to be news. Rather it's a piece of history. But any academic analysis of what happened should be drawing upon numerous sources; again looking to develop that synthesized broader understanding of what took place by considering numerous pieces of evidence: first-hand accounts, reporting of the event, immediate analysis, and any subsequent research or inquiry. In that regard it ought to provide our most thorough understanding to date as to what actually took place.

The story has built up like a jigsaw: piece after piece has given us more and more clarity over what occurred. But the jigsaw will never be finished. First-hand witnesses will forget the details of what they saw and whole pieces of the picture will be lost. New insights may come along that cast doubt on the original findings, furthering the scholarly conversation: a piece of the jigsaw that looked like it was part of the sky turns out to be part of the lake, and a hundred journal articles follow in its wake.

Throughout the lifetime of this story, we need to be aware of how partial our picture is. There's always going to be a tradeoff between immediacy and detail: we want to know what's happening right now, but we don't yet have the data to get a fully-informed understanding. And so much of human knowledge is bound up in these principles, from reading tweets and watching the news, to conducting research and writing academic papers. All geese are greylags until we see a Canada goose and have to revise our theory; our observations are only part of the jigsaw, and even the pieces we've got might not go where we think they do.

Two jigsaw pieces: one with Central Hall, the other with a face-palming greylag

Citation and evidence

"There's a goose in the library."

It's plausible, given the number of geese on campus. But could it really get through the gauntlet of all of those doors?

"I've just seen a goose in the library."

A first-hand account... can we believe this eye-witness?

"I've just seen a goose in the library. And so did Siobhan."

Let's face it, Siobhan's a far more credible witness. But now I have to believe two claims: not only that you saw a goose in the library, but that Siobhan saw it too. If only Siobhan were here to verify this claim.

"There's a goose in the library; the library just tweeted about it."

An authoritative source: the Library itself is tweeting that there's a goose in the library. If only I had some way of checking that... Oh, wait, I do! I can check Twitter. But where abouts on Twitter?

"There's a goose in the library; here, look at all these tweets about it!"

Oh yes, that's a lot of tweets... with photos too! Ok, I believe you.


Something is more believable if there is corroborating evidence. And the more corroborating evidence the better. I believe in the existence of koalas, despite never having seen one, because there is a huge weight of evidence to suggest that they are real. Whereas I am less inclined to believe in the existence of chupacabras.

The more outlandish my claim, the more I need to provide corroborating evidence for it to be believable. By citing evidence, I am able to demonstrate the validity of my claim, and you can 'follow up' that evidence as required.


Citing a source also acknowledges it: "I didn't see the goose, but Siobhan did," acknowledges Siobhan's achievement in observing that goose. If I fail to acknowledge Siobhan's role it looks like I'm trying to pass off their goose-spotting feat as my own, and that's called plagiarism.

Continuing the conversation

We might think about academic writing as contributing to a larger 'conversation' on a topic: we will need to refer back to previous research in order to build upon it, develop its ideas, or even argue against it. Our writing will reference earlier works, and, who knows, maybe somebody further along the line will cite what we've written too, carrying on the conversation further and acknowledging our own part within it!

This approach is also helpful in terms of our own research. We can use the references in an article to dig deeper into a topic, and some databases will let you trace a text forward in time, too, as it gets cited elsewhere (citation searching). Even something like a Wikipedia article can be a rich source of references to academic writing on a subject.

Constructing a citation

When we cite something, we need to provide enough information for somebody else to be able to find that thing and refer back to it. The sort of information we might need in order to be able to successfully find something will vary depending on what type of thing it is, and potentially even on the subject matter. To standardise this process and make sure that all the relevant information is included, different subject areas will use different referencing styles. These styles present the necessary information (the reference) in a consistent order (with specific punctuation and formatting). Take a look at our referencing styles Practical Guide for help and advice on creating appropriate references in your own work:

Something I saw on the internet...

There's a lot of rubbish online. There's a lot of rubbish published more generally, for that matter. "Something I heard in the pub" is probably not a good indicator of credibility. The same has become true of "something I saw on the internet". In what is still a relatively new medium, the codes and signifiers of what constitutes a reputable source are still somewhat muddy, which is in part why fake news stories have been able to outperform mainstream media in terms of Facebook shares. Such 'fake news' can take many forms:

  • satire or parody - no intention to cause harm but has potential to fool
  • false connection - when headlines, visuals or captions don’t support the content
  • misleading content - misleading use of information to frame an issue or an individual
  • false content - when genuine content is shared with false contextual information
  • imposter content - when genuine sources are impersonated
  • manipulated content - when genuine information or imagery is manipulated to deceive
  • fabricated content - new content is 100% false, designed to deceive and do harm

Take a look at the IFLA's guide to spotting fake news, and have a go for yourself on the Factitious game, below:

Credible sources

What makes a reliable source of information, and how might we use such sources in support of an argument? In this session we explore frameworks for evaluating information and determining credibility, and we apply these to a resource with which we are all familiar: Wikipedia. We learn the basics of editing Wikipedia and try to add some much-needed citations by evaluating information from appropriately credible sources.

Finding the right reading

When you do a Google search or a search in the library, you will get a massive reading list. How do you choose which are the best texts? Who do you trust? Where do you get the most reliable data from? In this session you will learn how to select the most appropriate reading for the task you have to complete.

Data literacy

Numbers surround us: in news headlines, in journal articles, in textbooks, in our own research data... In this session, in collaboration with the Maths Skills Centre, we'll take a look at how to make sense of the statistics we find, so that we can make sure we're not misled.


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