Three Common Methods For Web Data Extraction

Three Common Methods For Web Data Extraction

Probably the most common technique used traditionally to extract data from web pages this is to cook up some regular expressions that match the pieces you want (e.g., URL's and link titles). Our screen-scraper software actually started out as an application written in Perl for this very reason. In addition to regular expressions, you might also use some code written in something like Java or Active Server Pages to parse out larger chunks of text. Using raw regular expressions to pull out the data can be a little intimidating to the uninitiated, and can get a bit messy when a script contains a lot of them. At the same time, if you're already familiar with regular expressions, and your scraping project is relatively small, they can be a great solution.

Other techniques for getting the data out can get very sophisticated as algorithms that make use of artificial intelligence and such are applied to the page. Some programs will actually analyze the semantic content of an HTML page, then intelligently pull out the pieces that are of interest. Still other approaches deal with developing "ontologies", or hierarchical vocabularies intended to represent the content domain.

There are a number of companies (including our own) that offer commercial applications specifically intended to do screen-scraping. The applications vary quite a bit, but for medium to large-sized projects they're often a good solution. Each one will have its own learning curve, so you should plan on taking time to learn the ins and outs of a new application. Especially if you plan on doing a fair amount of screen-scraping it's probably a good idea to at least shop around for a screen-scraping application, as it will likely save you time and money in the long run.

So what's the best approach to data extraction? It really depends on what your needs are, and what resources you have at your disposal. Here are some of the pros and cons of the various approaches, as well as suggestions on when you might use each one:

Raw regular expressions and code

Advantages:

- If you're already familiar with regular expressions and at least one programming language, this can be a quick solution.

- Regular expressions allow for a fair amount of "fuzziness" in the matching such that minor changes to the content won't break them.

- You likely don't need to learn any new languages or tools (again, assuming you're already familiar with regular expressions and a programming language).

- Regular expressions are supported in almost all modern programming languages. Heck, even VBScript has a regular expression engine. It's also nice because the various regular expression implementations don't vary too significantly in their syntax.

Disadvantages:

- They can be complex for those that don't have a lot of experience with them. Learning regular expressions isn't like going from Perl to Java. It's more like going from Perl to XSLT, where you have to wrap your mind around a completely different way of viewing the problem.

- They're often confusing to analyze. Take a look through some of the regular expressions people have created to match something as simple as an email address and you'll see what I mean.

- If the content you're trying to match changes (e.g., they change the web page by adding a new "font" tag) you'll likely need to update your regular expressions to account for the change.

- The data discovery portion of the process (traversing various web pages to get to the page containing the data you want) will still need to be handled, and can get fairly complex if you need to deal with cookies and such.

When to use this approach: You'll most likely use straight regular expressions in screen-scraping when you have a small job you want to get done quickly. Especially if you already know regular expressions, there's no sense in getting into other tools if all you need to do is pull some news headlines off of a site.

Ontologies and artificial intelligence

Advantages:

- You create it once and it can more or less extract the data from any page within the content domain you're targeting.

- The data model is generally built in. For example, if you're extracting data about cars from web sites the extraction engine already knows what the make, model, and price are, so it can easily map them to existing data structures (e.g., insert the data into the correct locations in your database).

- There is relatively little long-term maintenance required. As web sites change you likely will need to do very little to your extraction engine in order to account for the changes.

Disadvantages:

- It's relatively complex to create and work with such an engine. The level of expertise required to even understand an extraction engine that uses artificial intelligence and ontologies is much higher than what is required to deal with regular expressions.

- These types of engines are expensive to build. There are commercial offerings that will give you the basis for doing this type of data extraction, but you still need to configure them to work with the specific content domain you're targeting.

- You still have to deal with the data discovery portion of the process, which may not fit as well with this approach (meaning you may have to create an entirely separate engine to handle data discovery). Data discovery is the process of crawling web sites such that you arrive at the pages where you want to extract data.

When to use this approach: Typically you'll only get into ontologies and artificial intelligence when you're planning on extracting information from a very large number of sources. It also makes sense to do this when the data you're trying to extract is in a very unstructured format (e.g., newspaper classified ads). In cases where the data is very structured (meaning there are clear labels identifying the various data fields), it may make more sense to go with regular expressions or a screen-scraping application.

Screen-scraping software

Advantages:

- Abstracts most of the complicated stuff away. You can do some pretty sophisticated things in most screen-scraping applications without knowing anything about regular expressions, HTTP, or cookies.

- Dramatically reduces the amount of time required to set up a site to be scraped. Once you learn a particular screen-scraping application the amount of time it requires to scrape sites vs. other methods is significantly lowered.

- Support from a commercial company. If you run into trouble while using a commercial screen-scraping application, chances are there are support forums and help lines where you can get assistance.

Disadvantages:

- The learning curve. Each screen-scraping application has its own way of going about things. This may imply learning a new scripting language in addition to familiarizing yourself with how the core application works.

- A potential cost. Most ready-to-go screen-scraping applications are commercial, so you'll likely be paying in dollars as well as time for this solution.

- A proprietary approach. Any time you use a proprietary application to solve a computing problem (and proprietary is obviously a matter of degree) you're locking yourself into using that approach. This may or may not be a big deal, but you should at least consider how well the application you're using will integrate with other software applications you currently have. For example, once the screen-scraping application has extracted the data how easy is it for you to get to that data from your own code?

When to use this approach: Screen-scraping applications vary widely in their ease-of-use, price, and suitability to tackle a broad range of scenarios. Chances are, though, that if you don't mind paying a bit, you can save yourself a significant amount of time by using one. If you're doing a quick scrape of a single page you can use just about any language with regular expressions. If you want to extract data from hundreds of web sites that are all formatted differently you're probably better off investing in a complex system that uses ontologies and/or artificial intelligence. For just about everything else, though, you may want to consider investing in an application specifically designed for screen-scraping.

As an aside, I thought I should also mention a recent project we've been involved with that has actually required a hybrid approach of two of the aforementioned methods. We're currently working on a project that deals with extracting newspaper classified ads. The data in classifieds is about as unstructured as you can get. For example, in a real estate ad the term "number of bedrooms" can be written about 25 different ways. The data extraction portion of the process is one that lends itself well to an ontologies-based approach, which is what we've done. However, we still had to handle the data discovery portion. We decided to use screen-scraper for that, and it's handling it just great. The basic process is that screen-scraper traverses the various pages of the site, pulling out raw chunks of data that constitute the classified ads. These ads then get passed to code we've written that uses ontologies in order to extract out the individual pieces we're after. Once the data has been extracted we then insert it into a database.

Source: http://ezinearticles.com/?Three-Common-Methods-For-Web-Data-Extraction&id=165416

Scraping data from LinkedIn

Scraping data from LinkedIn

How to scrape data from LinkedIn public profile for marketing purposes?

You can scrape data from a LinkedIn public profile using data scraper software. LinkedIn data extraction is most beneficial for marketers and most medium size companies rely on LinkedIn for their marketing purpose.

I would recommend you to use "LinkedIn Lead Extractor" software, which helps to quickly scrape public profiles from LinkedIn. With this tool your can scrape profile link, First Name, Last Name, Email, Phone Address, Twitter id, Yahoo messenger id, Skype Id, Google Talk ID, Job Role, Company Name, Address, Country, Connections. This company has built this tool specially for LinkedIn marketers who are not satisfied with their drop ship supplier's digital data.

LinkedIn advance search provides you the targeted customers profiles list with your requirements like country, country, city, company, job title, and much more.

In few weeks you can developed new ways to set-up differently the sales teams and create a much more technologic environment in the strategy department. An internal platform that generated targeted leads can be of a very big help. You can easily execute go to market to any area or city in so much little time compared with some years ago.

Source: http://www.ahmadsoftware.com/blogs/4/scraping-data-from-linkedin.html

Content Scrapers – How to Find Out Who is Stealing Your Content & What to Do About It

If you have been blogging for a while, chances are you are familiar with content scrapers. Content scrapers are websites that steal your content for their own blogs without your permission. Some content scrapers will just copy the content off of your blog, but most use automated software that takes the content from your RSS feed and posts your content to their site like it is a new post.

In this post, we are going to look at some potential link building benefits to content scrapers, how to find out what sites are scraping your content, and what you can do if you want to either benefit from the linking standpoint or have them take it down.

Linking Benefits of Content Scrapers

Last week, I was happy to see that I was listed in ProBlogger’s 20 Bloggers to Watch in 2012. Within 24 hours, I received a notification in my WordPress dashboard that a page on my blog had been linked to in the post on ProBlogger’s site.

After receiving the original notification from the ProBlogger post, I also received another 18 trackbacks from sites that had stolen the content in their post verbatim. Trackbacks are WordPress’ way of letting you know that another website has linked to a post on your blog. In this case, these 18 sites had posted the content exactly like the original post – with the links back to my blog still intact.

It was then that I started contemplating the potential link building benefits of content scrapers. These are not by any means quality links – the highest Google PageRank was a PR 2 domain, many were stealing content in a variety of languages, and one even had the nerve to use some kind of redirection script to take away the link juice of outgoing links! So while these links didn’t have the same authority that the original post had, they still count as links.

How to Catch Content Scrapers

Unfortunately, unless you want to continuously search for your post titles in Google, you’ll only be able to easily track down sites that keep your in-content links active. If you want to know what websites are scraping your content, here are a few tips to sniff them out.

Copyscape

Copyscape is a simple search engine that allows you to enter the URL of your content to find out if there are duplicates of it on the Internet. You can get a few results using their free search, or you can pay for a premium account to check up to 10,000 pages on your site and more.

Trackbacks

The first way is through your trackbacks in WordPress (as shown in the image above). Many of these will show up in the spam folder if you use Akismet. The key to getting trackbacks to appear from content scrapers is to always include links to other posts in your content. Be sure those links have great anchor text too, if you’re going for a little extra link juice. And even if you are not, internal linking with strong anchor text is good for your on-site optimization too!

Anyone thinking about link building benefits at this point is probably noting the sheer volume of links from these sites, some of which are content scrapers. Essentially any site that is linking to a lot of your posts that isn’t a social network, social bookmarking site, or a die-hard fan who just loves linking to you is potentially a content scraper. You’ll have to go to their website to be sure. To find your links on their site, click on one of the domains to see the details of what pages on your site they are linking to specifically.

You can see here that they are just blatantly copying my posts titles. When I visited one of the links, sure enough, they are copying my entire posts in their full glory onto their site.

Google Alerts

If you don’t post often or want to keep up with any mentions of your top blog posts on other websites, you can create a Google Alert using the exact match for your post’s title by putting the title in quotation marks.

I deliver all of my Google Alerts to an RSS feed so I can manage them in Google Reader, but you can also have them delivered regularly by email. You’ll even get an instant preview of the types of results you will get.

How to Get Credit for Scraped Posts

If you use WordPress, then you definitely want to try out the RSS footer plugin. This plugin allows you to place a custom piece of text at the top or bottom of your RSS feed content.
As you can see, even if you aren’t using it for the purpose of getting credit back to your posts when content thieves steal it, you can still use it for a little extra bit of advertising with the possible benefit of people who subscribe to your RSS feed clicking through to your website or social profiles. And when someone does scrape your content from your RSS feed, it shows up there too

So in the event that someone finds your scraped content, they will hopefully notice the credit before assuming it was created by the blog that stole it. If you don’t have WordPress, you can simply include a note at the top or bottom of your content that includes the same information.

How to Stop Content Scrapers

If you’re not interested in anyone copying your content, then you have a few options to choose from. You can start by contacting the site that is stealing your content and sending them a notice that you want all of your content removed immediately. You can do this through the site’s contact form, email address, or post it to any social accounts they list.

If there is no contact information on the website stealing your content, you can do a Whois Lookup to (hopefully) find out who owns the domain.

If it is not privately registered, you should find an administrative contact’s email address. If not, you should at least see the domain registrar which, in this case, is GoDaddy and/or the hosting company for the website which, in this case, is HostGator. You can try to contact both companies (HostGator has a DMCA form and GoDaddy has an email) and let them know that the domain in question is stealing copyrighted content in hopes that the website will be suspended or removed.

You can also visit the DMCA and use their takedown services to remove anyone who is copying your photos, video, audio, blog, or other content. They even offer a WordPress plugin to incorporate a DMCA protected badge on your site to warn potential thieves.

Have you ever dealt with content scrapers and thieves? Do you leave it alone for the link benefits, or do you fight back? What other tools, services, or other preventative tactics do you use to block content scrapers? Please share your thoughts and experiences in the comments!

Source URL : https://blog.kissmetrics.com/content-scrapers/

Data Scraping – Will Definitely Benefit a Business Startup

With increasingly data shared using internet, the data collected as well as the usage cases are increasing with an unbelievable pace. We’ve entered into the “Big Data” age and data scraping is among the resources to supply big data engines, the latest data for analytical analytics, contest monitoring, or just to steal the data.

From the technology viewpoint, competent data scraping is fairly complicated. It has many open-source projects that allow anybody to run a web data scraper through him. Nevertheless it’s the entire different story while it needs to be an interior of the business as well as that you require not only maintaining your scrapers but also scaling them as well as extract the data smartly as you need.

That is the reason why different services are selling the “data scraping” as service. Their work is taking care about all the technical characteristics so that you can have the data required without any industrial knowledge. Fundamentally all these startups pay attention for collecting the data and then extract its value for selling it to the customers.

Let’s take some examples:

• Sales Intelligence – The scrapers monitor competitors, marketplaces, online directories, and data from the public markets to discover leads. For instance, some tool’s track websites that drop or add JavaScript tags from the competitors therefore you can call them as eligible leads.
• Price Intelligence – A very ordinary use is the price monitoring. If this is in with e-commerce, travel, or property industry monitoring competitors’ prices as well as adjusting yours consequently is generally the key. All these services monitor the prices and using the analytical algorithms they may provide you advice about where the puck can be.
• Marketing – Data scraping may also be used for monitoring how the competitors are doing. From the reviews they have on the marketplaces to get coverage as well as financially published data one can find out a lot. Concerned about marketing, there is a development hacking class which teaches how to use scraping for the marketing objectives.

Finance intelligence, economic intelligence, etc have more and more financial, political, and economical data accessible online with the newer type of services that collect and add up of that, are increasing.

Let’s go through some points concerned with the market:

• It’s tough to evaluate how huge the data scraping market is as this is with the intersection of many big industries like sales, IT security, finance and marketing intelligence. This method is certainly a small part of all these industries however is expected to increase in the coming years.
• It’s a secured bet to indicate that increasingly SaaS will get pioneering applications for the web data scraping as well as progressively startups will use data scraping services from the safety viewpoint.
• As all the startups are generally entering huge markets using niche products / approaches (web data scraping isn’t a solution of everything, it’s more like a feature) they are expected to be obtained by superior players (within the safety, sales, or marketing tools industries). The technological barriers are also there.

Source URL : http://www.3idatascraping.com/data-scraping-will-definitely-benefit-a-business-startup.php

Data Scraping - What Are Hand-Scraped Hardwood Floors and What Are the Benefits?

If you love the look of hardwood flooring with lots of character, then you may want to check out hand-scraped hardwood flooring. Hand-scraped wood provides a warm vintage look, providing the floor instant character. These types of scraped hardwoods are suitable for living rooms, dining rooms, hallways and bedrooms. But what exactly is hand-scraped hardwood flooring?

Well, it is literally what you think it is. Hand-scraped hardwood flooring is created by hand using specialized wood working tools to make each board unique and giving an overall "old worn" appearance.

At Innovation Builders we offer solid wood floors finished on site with an actual hand-scraping technique followed by stain and sealer. Solid wood floors are installed by an expert team of technicians who work each board with skilled craftsman-like attention to detail. Following the scraping procedure the floor is stained by hand with a customer selected stain color, and then protected with multiple coats of sealing and finishing polyurethane. This finishing process of staining, sealing and coating the wood floors contributes to providing the look and durability of an old reclaimed wood floor, but with today's tough, urethane finishes.

There are many, many benefits to hand-scraped wood flooring. Overall, these floors are extremely durable and hard wearing, providing years of trouble-free use. These wood floors remain looking newer for longer because the texture that the process provides hides the typical dents, dings and scratches that other floors can't hide so easily. That's great news for households with kids, dogs, and cats.

These types of wood flooring have another unique advantage as well. When you do scratch these floors during their lifetime, the scratches are easily repaired. As long as the scratch isn't too deep you can make them practically disappear without ever having to hire a professional. It's simple to hide the scratch by using a color-matched stain marker or repair kit that is readily available through local flooring distributors. These features make hand-scraped hardwood flooring a lot more durable and hassle-free to maintain than other types of wood flooring.

The expert processes utilized in the creation of these floors provides a custom look of worn wood with deep color and subtle highlights. When the light hits the wood at different times during the day, it provides an understated but powerful effect of depth and beauty. They instantly offer your rooms a rustic look full of character, allowing your home to become a warm and inviting environment. The rustic look of this wood provides a texture, style and rustic appeal that cannot be matched by any other type of flooring.

Hand-Scraped Hardwood Flooring is a floor that says welcome and adds a touch of elegance to any home. If you are looking to buy a new home and you haven't had the opportunity to see or feel hand scraped hardwoods, stop in any of the model homes at Innovation Builders in Keller, North Richland Hills or Grand Prairie, Texas and check it out!

Source URL :   http://yellowpagesdatascraping.blogspot.in/2015/06/data-scraping-what-are-hand-scraped.html

Increasing Accessibility by Scraping Information From PDF

You may have heard about data scraping which is a method that is being used by computer programs in extracting data from an output that comes from another program. To put it simply, this is a process which involves the automatic sorting of information that can be found on different resources including the internet which is inside an html file, PDF or any other documents. In addition to that, there is the collection of pertinent information. These pieces of information will be contained into the databases or spreadsheets so that the users can retrieve them later.

Most of the websites today have text that can be accessed and written easily in the source code. However, there are now other businesses nowadays that choose to make use of Adobe PDF files or Portable Document Format. This is a type of file that can be viewed by simply using the free software known as the Adobe Acrobat. Almost any operating system supports the said software. There are many advantages when you choose to utilize PDF files. Among them is that the document that you have looks exactly the same even if you put it in another computer so that you can view it. Therefore, this makes it ideal for business documents or even specification sheets. Of course there are disadvantages as well. One of which is that the text that is contained in the file is converted into an image. In this case, it is often that you may have problems with this when it comes to the copying and pasting.

This is why there are some that start scraping information from PDF. This is often called PDF scraping in which this is the process that is just like data scraping only that you will be getting information that is contained in your PDF files. In order for you to begin scraping information from PDF, you must choose and exploit a tool that is specifically designed for this process. However, you will find that it is not easy to locate the right tool that will enable you to perform PDF scraping effectively. This is because most of the tools today have problems in obtaining exactly the same data that you want without personalizing them.

Nevertheless, if you search well enough, you will be able to encounter the program that you are looking for. There is no need for you to have programming language knowledge in order for you to use them. You can easily specify your own preferences and the software will do the rest of the work for you. There are also companies out there that you can contact and they will perform the task since they have the right tools that they can use. If you choose to do things manually, you will find that this is indeed tedious and complicated whereas if you compare this to having professionals do the job for you, they will be able to finish it in no time at all. Scraping information from PDF is a process where you collect the information that can be found on the internet and this does not infringe copyright laws.

 Source  URL : http://ezinearticles.com/?Increasing-Accessibility-by-Scraping-Information-From-PDF&id=4593863

Web Scraping to Create Open Data

Open data is the idea that some data should be freely available to everyone to use and republish as they wish, without restrictions from
copyright, patents or other mechanisms of control.

My first experience with open data was in the year 2010. I wanted to create a better app for Bicing, the local bike sharing system in
Barcelona. Their website was a nightmare to use and I was tired of needing to walk to each station, trying to guess which ones had bicycles.
There was no app for Android, other than a couple of unofficial attempts that didn’t work at all.

I began as most would; I searched the internet and found a library named python-bicing that was somehow able to retrieve station and
bike information. This was my first time using Python and, after some investigation, I learned what the code was doing: accessing the
official website, parsing the JavaScript that generated their buggy map and giving back a nice chunk of Python objects that represented
bike share stations.

This I learned was called web scraping. It was like I had figured out a magic trick that would allow me to always be able to access the data I
needed without having to rely on faulty websites.

The rise of OpenBicing and CityBikes

Shortly after, I launched OpenBicing, an Android app for the local bike sharing system in Barcelona, together with a backend that used
python-bicing. I also shared a public API that provided this information so that nobody else had to do the dirty work ever again.

Since other cities were having the same problem, we expanded the scope of the project worldwide and renamed it CityBikes. That was 6
years ago.

To date, CityBikes is the most comprehensive and widely used open API for bike sharing information, with support for over 400 cities
worldwide. Our API processes around 10 requests per second and we scrape each of the 418 feeds about every three minutes. Making our
core library available for anyone to contribute has been crucial in maintaining and adding coverage for all of the supported systems.

The open data fallacy

We are usually regarded as “an open data project” even though less than 10% of our feeds come from properly licensed, documented and
machine-readable feeds. The remaining 90% is composed of 188 feeds that are machine-readable, but not licensed nor documented and
230 that are entirely maintained by scraping HTML pages.

North American BikeShare Association) recently published GBFS (General Bikeshare Feed Specification). This is clearly a step in the right
direction, but I can’t help but look at the almost 60% of services we currently support through scraping and wonder how long it will take the
remaining organizations to release their information, if ever. This is even more the case considering these numbers aren’t even taking into
account worldwide coverage.

Over the last few years there has been a progression by transportation companies and city councils toward providing their information as
“open data”. Directive 2003/98/EC encourages EU member states to release information regarding public services.

Yet, in most cases, there’s little action in enforcing Public Private Partnerships (PPP) to release their public information under a non-
restrictive license or even to transfer ownership of the data to city councils to be included in their open data portals.

Even with the increasing number of companies and institutions interested in participating in open data, by no means should we consider
open data a reality or something to be taken for granted. I firmly believe in the future and benefits of open data, I have seen them
happening all around CityBikes, but as technologists we need to stress the fact that the data is not out there yet.

The benefits of open data

When I started this project, I sought to make a difference in Barcelona. Now you can find tons of bike sharing apps that use our API on all
major platforms. It doesn’t matter that these are not our own apps. They are solving the same problem we were trying to fix, so their
success is our success.

Besides popular apps like Moovit or CityMapper, there are many neat projects out there, some of which are published under free software
licenses. Ideally, a city council could create a customization of any of these apps for their own use.

Most official applications for bike sharing systems have terrible ratings. The core business of transportation companies is running a service,

so they have no real motivation to create an engaging UI or innovate further. In some cases, the city council does not even own the rights to
the data, being completely at the mercy of the company providing the transportation service.

Open data over apps

When providing public services, city councils and companies often get lost in what they should offer as an aid to the service. They focus on
a nice map or a flashy application, rather than providing the data behind these service aids. Maps, apps, and websites have a limited focus
and usually serve a single purpose. On the other hand, data is malleable and the purest form of representation. While you can’t create
something new from looking and playing with a static map (except, of course, if you scrape it), data can be used to create countless
different iterations. It can even provide a bridge that will allow anyone to participate, improve and build on top of these public services.

Wrap Up

At this point, you might wonder why I care so much about bike sharing. To me it’s not about bike sharing anymore. CityBikes is just too
good of an open data metaphor, a simulation in which public information is freely accessible to everyone. It shows the benefits of open
data and the deficiencies that arise from the lack thereof.

We shouldn’t have to create open data by scraping websites. This information should be already available, easily accessed and provided in
a machine-readable format from the original providers, be they city councils or transportation companies. However, until there’s another
option, we’ll always have scraping.


Source : https://blog.scrapinghub.com/2016/03/30/web-scraping-to-create-open-data/