BootCaT front-end tutorial - Part 3

Back to part 2 of the tutorial

Collect URLs

It's time to query the search engine using the tuples we generated earlier. What happens here is that we search the web via the search engine, looking for pages that contain the tuples (combinations of our seeds) that were generated in the previous step. This identifies texts that are relevant to the more or less specific corpus (domain) in which we are interested, based on how specialized or general the seeds are.

The search engine will return only a limited number of pages for each query (i.e. tuple) we submit; the default value is 10 URLs per query and we won't change it.

Increasing the number of pages will result in a larger corpus, but its contents will tend to become less relevant.

Click “Collect URLs” to start collecting URLs from the search engine. This might take a while, depending on Internet traffic and speed of your connection.

In this step we only collect the URLs (i.e. the Internet addresses) of pages, the actual pages will be downloaded in a later step.

Edit the URL list

Now you can manually edit the list of URLs. We won't do it here, but if you want to give it a try just de-select the box “I'm done editing URLs” to activate the text box and start editing (i.e. deleting the line of text with each URL that you would like to remove). Check the box again when you're done.

Notice how the total number of collected URLs appears to be wrong: we generated 15 queries and instructed BootCaT to retrieve 10 URLs per query, so the total should be 150. What happened then? Simple, quite a few URLs where retrieved more than once (this is because the queries can be very similar to one another, as the tuples overlap to a large extent) and duplicates were automatically eliminated by BootCaT.

Click “Next”.

Build corpus

This is the final step.

Not only will the pages be downloaded, they will also be automatically cleaned:

HTML code will be removed

boilerplate (i.e. things like menus, navigation bars, ads, disclaimers, automatic error messages) will be stripped

The purpose of this stage is to get rid of elements which are part of the downloaded web pages, but that are very unlikely to be of interest to corpus users. However, since this process is automated, the cleaning process is far from perfect, so be aware that some unwanted elements will still be present in the corpus.

Click on “Build corpus” to start the corpus creation process. This will take a while, depending on Internet traffic, connection speed and number of URLs to download.

Once the download is complete click “Open corpus folder”.

The contents of the folder where the corpus data is stored will be displayed.

What now?

Congratulations, you have created your first web corpus!

Now you can use your favourite corpus analysis tools to work with your corpus, here's a list of programs you might find useful.

If you want to manually inspect the corpus you just created, there are a number of text editors you can use. If you're on Mac or Linux you already have everything you need, if you're on Windows we strongly recommend the free Notepad++ since the default Windows Notepad will not display the corpus correctly.

Not happy with your corpus?

If you're happy with the corpus that you have created, then go ahead and have fun using it! Otherwise, if the semi-automatically built corpus does not meet your requirements, repeat the procedure providing a different set of seeds (e.g. more seeds to make the corpus more specific and focussed), and/or modify the parameters subsequently used to generate the tuples.