What you have to know before requesting web scraping services?

Before you request web scraping services you have to know what are your needs (what data you need, structure of it and where you can find this data).

Step 1: Define what data you need?
Data needs depending on purpose, if you want to find new customers you probably need contact data from players in your industry. Also if you want to study your competitors you need to define who are they. Only after that you can select data sources (websites feeds or other electronic sources) for this extraction.

In many cases for discovering and defining data sources are used search engines like Google, Bing, Yahoo, and others.

Step 2: Structure of data

Data structure it’s directly linked to usage purpose. In many cases data structure it’s a table where a row represents an entity and a cell of this row represents a property of this entity. In other cases Data structure is a a chart or another graphic representation builder with data extracted from a web source.

Step 3: Number of data extraction

In many cases is needed one time data extraction. In other cases when you need a regular report, are needed periodically extractions.

If you have defined all of above points you are ready to request a quote and an amount estimation from this contact form.

Source: http://thewebminer.com/blog/2013/08/

Scraping XML Tables with R

A couple of my good friends also recently started a sports analytics blog. We’ve decided to collaborate on a couple of studies revolving around NBA data found at www.basketball-reference.com. This will be the first part of that project!

Data scientists need data. The internet has lots of data. How can I get that data into R? Scrape it!

People have been scraping websites for as long as there have been websites. It’s gotten pretty easy using R/Python/whatever other tool you want to use. This post shows how to use R to scrape the demographic information for all NBA and ABA players listed at www.basketball-reference.com.

Here’s the code:

###### Settings

library(XML)

 ###### URLs

url<-paste0("http://www.basketball-reference.com/players/",letters,"/")

len<-length(url)

 ###### Reading data

tbl<-readHTMLTable(url[1])[[1]]

 for (i in 2:len)

    {tbl<-rbind(tbl,readHTMLTable(url[i])[[1]])}

 ###### Formatting data

colnames(tbl)<-c("Name","StartYear","EndYear","Position","Height","Weight","BirthDate","College")

tbl$BirthDate<-as.Date(tbl$BirthDate[1],format="%B %d, %Y")

Created by Pretty R at inside-R.org

And here’s the result:Result

Source: http://www.r-bloggers.com/scraping-xml-tables-with-r/

Data Mining KNN Classifier

Q1   

Suppose a data analyst working for an insurance company was asked to build a predictive model for predicting weather a customer will buy a mobile home insurance policy. S/he tried kNN classifier with different number of neighbours (k=1,2,3,4,5). S/he got the following F-scores measured on the training data: (1.0; 0.92; 0.90; 0.85; 0.82). Based on that the analyst decided to deploy kNN with k=1. Was it a good choice? How would you select an optimal number of neighbours in this case?

1 Answer

It is not a good idea to select a parameter of a prediction algorithm using the whole training set as the result will be biased towards this particular training set and has no information about generalization performance (i.e. performance towards unseen cases). You should apply a cross-validation technique e.g. 10-fold cross-validation to select the best K (i.e. K with largest F-value) within a range. This involves splitting your training data in 10 equal parts retain 9 parts for training and 1 for validation. Iterate such that each part has been left out for validation. If you take enough folds this will allow you as well to obtain statistics of the F-value and then you can test whether these values for different K values are statistically significant.

See e.g. also: http://pic.dhe.ibm.com/infocenter/spssstat/v20r0m0/index.jsp?topic=%2Fcom.ibm.spss.statistics.help%2Falg_knn_training_crossvalidation.htm

The subtlety here however is that there is likely a dependency between the number of data points for prediction and the K-value. So If you apply cross-validation you use 9/10 of the training set for training...Not sure whether any research has been performed on this and how to correct for that in the final training set. Anyway most software packages just use the abovementioned techniques e.g. see SPSS in the link. A solution is to use leave-one-out cross-validation (each data samples is left out once for testing) in that case you have N-1 training samples(the original training set has N).

Source:http://stackoverflow.com/questions/21121509/data-mining-knn-classifier?rq=1

Using Kimono Labs to Scrape the Web for Free

Historically, I have written and presented about big data—using data to create insights, and how to automate your data ingestion process by connecting to APIs and leveraging advanced database technologies.

Recently I spoke at SMX West about leveraging the rich data in webmaster tools. After the panel, I was approached by the in-house SEO of a small company, who asked me how he could extract and leverage all the rich data out there without having a development team or large budget. I pointed him to the CSV exports and some of the more hidden tools to extract Google data, such as the GA Query Builder and the YouTube Analytics Query Builder.

However, what do you do if there is no API? What do you do if you want to look at unstructured data, or use a data source that does not provide an export?

For today's analytics pros, the world of scraping—or content extraction (sounds less black hat)—has evolved a lot, and there are lots of great technologies and tools out there to help solve those problems. To do so, many companies have emerged that specialize in programmatic content extraction such as Mozenda, ScraperWiki, ImprtIO, and Outwit, but for today's example I will use Kimono Labs. Kimono is simple and easy to use and offers very competitive pricing (including a very functional free version). I should also note that I have no connection to Kimono; it's simply the tool I used for this example.

Before we get into the actual "scraping" I want to briefly discuss how these tools work.

The purpose of a tool like Kimono is to take unstructured data (not organized or exportable) and convert it into a structured format. The prime example of this is any ranking tool. A ranking tool reads Google's results page, extracts the information and, based on certain rules, it creates a visual view of the data which is your ranking report.

Kimono Labs allows you to extract this data either on demand or as a scheduled job. Once you've extracted the data, it then allows you to either download it via a file or extract it via their own API. This is where Kimono really shines—it basically allows you to take any website or data source and turn it into an API or automated export.

For today's exercise I would like to create two scrapers.

A. A ranking tool that will take Google's results and store them in a data set, just like any other ranking tool. (Disclaimer: this is meant only as an example, as scraping Google's results is against Google's Terms of Service).

B. A ranking tool for Slideshare. We will simulate a Slideshare search and then extract all the results including some additional metrics. Once we have collected this data, we will look at the types of insights you are able to generate.

1. Sign up

Signup is simple; just go to http://www.kimonolabs.com/signup and complete the form. You will then be brought to a welcome page where you will be asked to drag their bookmarklet into your bookmarks bar.

The Kimonify Bookmarklet is the trigger that will start the application.

2. Building a ranking tool

Simply navigate your browser to Google and perform a search; in this example I am going to use the term "scraping." Once the results pages are displayed, press the kimonify button (in some cases you might need to search again). Once you complete your search you should see a screen like the one below:

It is basically the default results page, but on the top you should see the Kimono Tool Bar. Let's have a close look at that:

The bar is broken down into a few actions:

    URL – Is the current URL you are analyzing.

    ITEM NAME – Once you define an item to collect, you should name it.

    ITEM COUNT – This will show you the number of results in your current collection.

    NEW ITEM – Once you have completed the first item, you can click this to start to collect the next set.

    PAGINATION – You use this mode to define the pagination link.

    UNDO – I hope I don't have to explain this ;)

    EXTRACTOR VIEW – The mode you see in the screenshot above.

    MODEL VIEW – Shows you the data model (the items and the type).

    DATA VIEW – Shows you the actual data the current page would collect.

    DONE – Saves your newly created API.

After you press the bookmarklet you need to start tagging the individual elements you want to extract. You can do this simply by clicking on the desired elements on the page (if you hover over it, it changes color for collectable elements).

Kimono will then try to identify similar elements on the page; it will highlight some suggested ones and you can confirm a suggestion via the little checkmark:

A great way to make sure you have the correct elements is by looking at the count. For example, we know that Google shows 10 results per page, therefore we want to see "10" in the item count box, which indicates that we have 10 similar items marked. Now go ahead and name your new item group. Each collection of elements should have a unique name. In this page, it would be "Title".

Now it's time to confirm the data; just click on the little Data icon to see a preview of the actual data this page would collect. In the data view you can switch between different formats (JSON, CSV and RSS). If everything went well, it should look like this:

As you can see, it not only extracted the visual title but also the underlying link. Good job!

To collect some more info, click on the Extractor icon again and pick out the next element.

Now click on the Plus icon and then on the description of the first listing. Since the first listing contains site links, it is not clear to Kimono what the structure is, so we need to help it along and click on the next description as well.

As soon as you do this, Kimono will identify some other descriptions; however, our count only shows 8 instead of the 10 items that are actually on that page. As we scroll down, we see some entries with author markup; Kimono is not sure if they are part of the set, so click the little checkbox to confirm. Your count should jump to 10.

Now that you identified all 10 objects, go ahead and name that group; the process is the same as in the Title example. In order to make our Tool better than others, I would like to add one more set— the author info.

Once again, click the Plus icon to start a new collection and scroll down to click on the author name. Because this is totally unstructured, Google will make a few recommendations; in this case, we are working on the exclusion process, so press the X for everything that's not an author name. Since the word "by" is included, highlight only the name and not "by" to exclude that (keep in mind you can always undo if things get odd).

Once you've highlighted both names, results should look like the one below, with the count in the circle being 2 representing the two authors listed on this page.

Out of interest I did the same for the number of people in their Google+ circles. Once you have done that, click on the Model View button, and you should see all the fields. If you click on the Data View you should see the data set with the authors and circles.

As a final step, let's go back to the Extractor view and define the pagination; just click the Pagination button (it looks like a book) and select the next link. Once you have done that, click Done.

You will be presented with a screen similar to this one:

Here you simply name your API, define how often you want this data to be extracted and how many pages you want to crawl. All of these settings can be changed manually; I would leave it with On demand and 10 pages max to not overuse your credits.

Once you've saved your API, there are a ton of options (too many to review here). Kimono has a great learning section you can check out any time.

To collect the listings requires a quick setup. Click on the pagination tab, turn it on and set your schedule to On demand to pull data when you ask it to. Your screen should look like this:

Now press Crawl and Kimono will start collecting your data. If you see any issues, you can always click on Edit API and go back to the extraction screen.

Once the crawl is completed, go to the Test Endpoint tab to view or download your data (I prefer CSV because you can easily open it in Excel, CSV, Spotfire, etc.) A possible next step here would be doing this for multiple keywords and then analyzing the impact of, say, G+ Authority on rankings. Again, many of you might say that a ranking tool can already do this, and that's true, but I wanted to cover the basics before we dive into the next one.

3. Extracting SlideShare data

With Slideshare's recent growth in popularity it has become a document sharing tool of choice for many marketers. But what's really on Slideshare, who are the influencers, what makes it tick? We can utilize a custom scraper to extract that kind data from Slideshare.

To get started, point your browser to Slideshare and pick a keyword to search for.

For our example I want to look at presentations that talk about PPC in English, sorted by popularity, so the URL would be:

http://www.slideshare.net/search/slideshow?ft=presentations&lang=en&page=1&q=ppc&qf=qf1&sort=views&ud=any

Once you are on that page, pick the Kimonify button as you did earlier and tag the elements. In this case I will tag:

    Title
    Description
    Category
    Author
    Likes
    Slides

Once you have tagged those, go ahead and add the pagination as described above.

That will make a nice rich dataset which should look like this:

Hit Done and you're finished. In order to quickly highlight the benefits of this rich data, I am going to load the data into Spotfire to get some interesting statics (I hope).

4. Insights

Rather than do a step-by-step walktrough of how to build dashboards, which you can find here, I just want to show you some insights you can glean from this data:

    Most Popular Authors by Category. This shows you the top contributors and the categories they are in for PPC (squares sized by Likes)

    Correlations. Is there a correlation between the numbers of slides vs. the number of likes? Why not find out?
    Category with the most PPC content. Discover where your content works best (most likes).

5. Output

One of the great things about Kimono we have not really covered is that it actually converts websites into APIs. That means you build them once, and each time you need the data you can call it up. As an example, if I call up the Slideshare API again tomorrow, the data will be different. So you basically appified Slisdeshare. The interesting part here is the flexibility that Kimono offers. If you go to the How to Use slide, you will see the way Kimono treats the Source URL In this case it looks like this:

The way you can pull data from Kimono aside from the export is their own API; in this case you call the default URL,

http://www.kimonolabs.com/api/YOURPAIID?apikey=YO...

You would get the default data from the original URL; however, as illustrated in the table above, you can dynamically adjust elements of the source URL.

For example, if you append "&q=SEO"

(http://www.kimonolabs.com/api/YOURPAIID?apikey=YOURAPIKEY&q=SEO)

you would get the top slides for SEO instead of PPC. You can change any of the URL options easily.

I know this was a lot of information, but believe me when I tell you, we just scratched the surface. Tools like Kimono offer a variety of advanced functions that really open up the possibilities. Once you start to realize the potential, you will come up with some amazing, innovative ideas. I would love to see some of them here shared in the comments. So get out there and start scraping … and please feel free to tweet at me or reply below with any questions or comments!

Source: http://moz.com/blog/web-scraping-with-kimono-labs

Web Scraping for SEO with these Open-Source Scrapers

When conducting Search Engine Optimization (SEO), we’re required to scrape websites for data, our campaigns, and reports for our clients. At the lowest level we utilize scraping to keep track of rankings on search engines like Google, Bing, and Yahoo, even keep a track of links on websites to know when it’s completed its lifespan. Then we’ve used them to help us aggregate data from APIs, RSS feeds, and websites to conduct some of our data mining to find patterns to help us become more competitive. 

So scraping is a function majority of companies (SEOmoz, Raventools, and Google) have to do to either save money, protect intellectual property, track trends, etc… Businesses can find infinite uses with scraping tools, it just depends if you’re an printed circuit board manufacturer looking for ideas on your e-mail marketing campaign or a Orange County based business trying to keep an eye out on the competition. which is why we’ve created a comprehensive list of open source scrapers out there to help all the businesses out there. Just keep in mind we haven’t used all of them!

Words of caution, web scrapers require knowledge specific to the language such as PHP & cURL. Take into considerations issues like cookie management, fault tolerance, organizing the data properly, not crashing the website being scraped, and making sure the website doesn’t prohibit scraping.

If you’re ready, here’s the list…

Erlang

    eBot

Java

    Heritrix
    Nutch
    Piggy Bank
    WebSPHINX
    WebHarvest

PHP

    PHPCrawl
    Snoopy
    SpiderMonkey

Python

    BeautifulSoap
    HarvestMan
    Scrape.py
    Scrapemark
    Scrapy **
    Mechanize

Ruby

    Anemone
    scRUBYt

We’ll come back and update this list as we encounter more! If you would like to submit a solution we missed, feel free. Also we’re looking for guides related to each of these, so if you know of any or would be interested in guesting blogging about one, let us know!

Source:http://www.annexcore.com/blog/web-scraping-for-seo-with-these-open-source-scrapers/

How to scrape data without coding? A step by step tutorial on import.io

Import.io (pronounced import-eye-oh) lets you scrape data from any website into a searchable database. It is perfect for gathering, aggregating and analysing data from websites without the need for coding skills. As Sally Hadadi, from Import.io, told Journalism.co.uk: the idea is to “democratise” data. “We want journalists to get the best information possible to encourage and enhance unique, powerful pieces of work and generally make their research much easier.” Different uses for journalists, supplemented by case studies, can be found here.

A beginner’s guide

After downloading and opening import.io browser, copy the URL of the page you want to scrape into the import.io browser. I decided to scrape the search results website of orphanages in London:

001 Orphanages in London

After opening the website, press the tiny pink button in top right corner of the browser and follow up with “Let’s get cracking!” in the bottom right menu which has just appeared.

Then, choose the type of scraping you want to perform. In my case, it’s a Crawler (we’ll be getting data from multiple similar pages on the same site):

crawler

And confirm the URL of the website you want to scrape by clicking “I’m there”.

As advised, choose “Detect optimal settings” and confirm the following:

data

In the menu “Rows per page” select the format in which data appears on the website, whether it is “single” or “multiple”. I’m opting for the multiple as my URL is a listing of multiple search results:multiple

Now, the time has come to “train your rows” i.e. mark which part of the website you are interested in scraping. Hover over an entire “entry” or “paragraph”:hover over entry

…and he entry will be highlighted in pink or blue. Press “Train rows”.

train rows

Repeat the operation with the next entry/paragraph so that the scraper gets the hang of the pattern of your selections. Two examples should suffice. Scroll down to the bottom of your website to make sure that all entries until the last one are selected (=highlighted in pink or blue alternately).

If it is, press “I’ve got all 50 rows” (the number depends on how many rows you have selected).

Now it’s time to focus on particular chunks of data you would like to extract. My entries consist of a name of the orphanage, address, phone number and a short description so I will extract all those to separate columns. Let’s start by adding a column “name”:

add column

Next, highlight the name of the first orphanage in the list and press “Train”.

highlighttrain

Your table should automatically fill in with names of all orphanages in the list:table name

If it didn’t, try tweaking your selection a bit. Then add another column “address” and extract the address of the orphanage by highlighting the two lines of addresses and “training” the rows.

Repeat the operation for a “phone number” and “description”. Your table should end up looking like this:table final

*Before passing on to the next column it is worth to check that all the rows have filled up. If not, highlighting and training of the individual elements might be necessary.

Once you’ve grabbed all that you need, click “I’ve got what I need”. The menu will now ask you if you want to scrape more pages. In this case, the search yielded two pages of search results so I will add another page. In order to this this, go back to your website in you regular browser, choose page 2 (or any next one) of your search results and copy the URL. Paste it into the import.io browser and confirm by clicking “I’m there”:

i'm there

The scraper should automatically fill in your table for page 2. Click “I’ve got all 45 rows” and “I’ve got what I needed”.

You need to add at least 5 pages, which is a bit frustrating with a smaller data set like this one. The way around it is to add page 2 a couple of times and delete the unnecessary rows in the final table.

Once the cheating is done, click “I’m done training!” and “Upload to import.io”.

upload

Give the name to your Crawler, e.g. “Orphanages in London” and wait for import.io to upload your data. Then, run crawler:run crawler

Make sure that the page depth is 10 and that click “Go”. If you’re scraping a huge dataset with several pages of search results, you can copy your URLs to Excel, highlight them and drag down with a black cross (bottom right of the cell) to obtain a comprehensive list. Paste it into the “Where to start?” window and press “Go”.go

crawlingAfter the crawling is complete, you can download you data in EXCEL, HTML, JSON or CSV.dataset

As a result, we obtain a data set which can be easily turned into a map of orphanages in London, e.g. using Google Fusion Tables.

Source:http://www.interhacktives.com/2014/03/06/scrape-data-without-coding-step-step-tutorial-import-io/

Is Web Scraping Legal?

Web scraping might be one of the best ways to aggregate content from across the internet, but it comes with a caveat: It’s also one of the hardest tools to parse from a legal standpoint.

For the uninitiated, web scraping is a process whereby an automated piece of software extracts data from a website by “scraping” through the site’s many pages. While search engines like Google and Bing do a similar task when they index web pages, scraping engines take the process a step further and convert the information into a format which can be easily transferred over to a database or spreadsheet.

It’s also important to note that a web scraper is not the same as an API. While a company might provide an API to allow other systems to interact with its data, the quality and quantity of data available through APIs is typically lower than what is made available through web scraping. In addition, web scrapers provide more up-to-date information than APIs and are much easier to customize from a structural standpoint.

The applications of this “scraped” information are widespread. A journalist like Nate Silver might use scrapers to monitor baseball statistics and create numerical evidence for a new sports story he’s working on. Similarly, an eCommerce business might bulk scrape product titles, prices, and SKUs from other sites in order to further analyze them.

Legality of Web ScrapingWhile web scraping is an undoubtedly powerful tool, it’s still undergoing growing pains when it comes to legal matters. Because the scraping process appropriates pre-existing content from across the web, there are all kinds of ethical and legal quandaries that confront businesses who hope to do leverage scrapers for their own processes.

In this “wild west” environment, where the legal implications of web scraping are in a constant state of flux, it helps to get a foothold on where the legal needle currently falls. The following timeline outlines some of the biggest cases involving web scrapers in the United States, and allows us to achieve a greater understanding on the precedents that surround the court rulings.

Terms of Use Tug-of-War—2000-2009

For years after they first came into use, web scrapers went largely unchallenged from a legal standpoint. In 2000, however, the use of scrapers came under heavy and consistent fire when eBay fired the first shot against an auction data aggregator called Bidder’s Edge. In this very early case, eBay argued that Bidder’s Edge was using scrapers in a way that violated Trespass to Chattels doctrine. While the lawsuit was settled out of court, the judge upheld eBay’s original injunction, stating that heavy bot traffic could very well disrupt eBay’s service.

Then in 2003’s Intel Corp. v. Hamidi, the California Supreme court overturned the basis of eBay v. Bidder’s Edge, ruling that Trespass to Chattels could not extend to the context of computers if no actual damage to personal property occurred.

So in terms of legal action against web scraping, Tresspass to Chattels no longer applied, and things were back to square one. This began a period in which the courts consistently rejected Terms of Service as a valid means of prohibiting scrapers, including cases like Perfect 10 v. Google, and Cvent v. Eventbrite.

The Takeaway: The earliest cases against scrapers hinged on Trespass to Chattels law, and were successful. However, that doctrine is no longer a valid approach.

Facebook Web Scraping2009—Facebook Steps In

In 2009, Facebook turned the tides of the web scraping war when Power.com, a site which aggregated multiple social networks into one centralized site, included Facebook in their service. Because Power.com was scraping Facebook’s content instead of adhering to their established standards, Facebook sued Power on grounds of copyright infringement.

In denying Power.com’s motion to dismiss the case, the Judge ruled that scraping can constitute copying, however momentary that copying may be. And because Facebook’s Terms of Service don’t allow for scraping, that act of copying constituted an infringement on Facebook’s copyright. With this decision, the waters regarding the legality of web scrapers began to shift in favor of the content creators.

The Takeaway: Even if a web scraper ignores infringing content on its way to freely-usable content, it might qualify as copyright infringement by virtue of having technically “copied” the infringing content first.

2011-2014— U.S. v Auernheimer

In 2010, hacker Andrew “Weev” Auernheimer found a security flaw in AT&T’s website, which would display the email addresses of users who visited the site via their iPads. By exploiting the flaw using some simple scripts and a scraper, Auernheimer was able to gather thousands of emails from the AT&T site.

Although these email addresses were publicly available, Auernheimer’s exploit led to his 2012 conviction, where he was charged with identity fraud and conspiracy to access a computer without authorization.

Data ScrapingEarlier this year, the court vacated Auernheimer’s conviction, ruling that the trial’s New Jersey venue was improper. But even though the case turned out to be mostly inconclusive, the court noted the fact that there was no evidence to show that “any password gate or code-based barrier was breached.” This seems to leave room for the web scraping of publicly-available personal information, although it’s still very much open to interpretation and not set in stone.

The Takeaway: Using a web scraper to aggregate sensitive personal information can lead to a conviction, even if that information was technically available to the public. While there is hope in the court’s observation that no passwords or barriers were broken to retrieve this information, the waters here are still very volatile.

2013—Associated Press vs. Meltwater

Meltwater is a software company whose “Global Media Monitoring” product uses scrapers to aggregate news stories for paying clients. The Associated Press took issue with Meltwater’s scraping of their original stories, some of which had been copyrighted. In 2012, AP filed suit against Meltwater for copy infringement and hot news misappropriation.

While it’s already been established that facts cannot be copyrighted, the court decided that the AP’s copyrighted articles—and more specifically, the way in which the facts within those articles were arranged—were not fair game for copying. On top of this, Meltwater’s use of the articles failed to meet the established fair use standards, and could not be defended on that front either.

The Takeaway: Fair use is limited when it comes to web scrapers, and copyrighted content is not always open to be scraped.

~~

By closely observing the outcomes of previous rulings, you’ll find that there are a few guidelines that a scraper should attempt to adhere to:

    Content being scraped is not copyright protected
    The act of scraping does not burden the services of the site being scraped
    The scraper does not violate the Terms of Use of the site being scraped
    The scraper does not gather sensitive user information
    The scraped content adheres to fair use standards

While all of these guidelines are important to understand before using scrapers, there are other ways to acclimate to the legal nuances. In many cases, you’ll find that a simple conversation with a business software developer or consultant will lead to some satisfying conclusions: Odds are, they’ve used scrapers in the past and can shed light on any snags they’ve hit in the process. And of course, talking with a lawyer is always an ideal course of action when treading into questionable legal territory.

Source:http://blog.icreon.us/2014/09/12/web-scraping-and-you-a-legal-primer-for-one-of-its-most-useful-tools/

Scraping Data: Site-specific Extractors vs. Generic Extractors

Scraping is becoming a rather mundane job with every other organization getting its feet wet with it for their own data gathering needs. There have been enough number of crawlers built – some open-sourced and others internal to organizations for in-house utilities. Although crawling might seem like a simple technique at the onset, doing this at a large-scale is the real deal. You need to have a distributed stack set up to take care of handling huge volumes of data, to provide data in a low-latency model and also to deal with fail-overs. This still is achievable after crossing the initial tech barrier and via continuous optimizations. (P.S. Not under-estimating this part because it still needs a team of Engineers monitoring the stats and scratching their heads at times).

Social Media Scraping

Focused crawls on a predefined list of sites

However, you bump into a completely new land if your goal is to generate clean and usable data sets from these crawls i.e. “extract” data in a format that your DB can process and aid in generating insights. There are 2 ways of tackling this:

a. site-specific extractors which give desired results

b. generic extractors that result in few surprises

Assuming you still do focused crawls on a predefined list of sites, let’s go over specific scenarios when you have to pick between the two-

1. Mass-scale crawls; high-level meta data - Use generic extractors when you have a large-scale crawling requirement on a continuous basis. Large-scale would mean having to crawl sites in the range of hundreds of thousands. Since the web is a jungle and no two sites share the same template, it would be impossible to write an extractor for each. However, you have to settle in with just the document-level information from such crawls like the URL, meta keywords, blog or news titles, author, date and article content which is still enough information to be happy with if your requirement is analyzing sentiment of the data.

cb1c0_one-size

A generic extractor case

Generic extractors don’t yield accurate results and often mess up the datasets deeming it unusable. Reason being

programatically distinguishing relevant data from irrelevant datasets is a challenge. For example, how would the extractor know to skip pages that have a list of blogs and only extract the ones with the complete article. Or delineating article content from the title on a blog page is not easy either.

To summarize, below is what to expect of a generic extractor.

Pros-

minimal manual intervention

low on effort and time

can work on any scale

Cons-

Data quality compromised

inaccurate and incomplete datasets

lesser details suited only for high-level analyses

Suited for gathering- blogs, forums, news

Uses- Sentiment Analysis, Brand Monitoring, Competitor Analysis, Social Media Monitoring.

2. Low/Mid scale crawls; detailed datasets - If precise extraction is the mandate, there’s no going away from site-specific extractors. But realistically this is do-able only if your scope of work is limited i.e. few hundred sites or less. Using site-specific extractors, you could extract as many number of fields from any nook or corner of the web pages. Most of the times, most pages on a website share similar templates. If not, they can still be accommodated for using site-specific extractors.

cutlery

Designing extractor for each website

Pros-

High data quality

Better data coverage on the site

Cons-

High on effort and time

Site structures keep changing from time to time and maintaining these requires a lot of monitoring and manual intervention

Only for limited scale

Suited for gathering - any data from any domain on any site be it product specifications and price details, reviews, blogs, forums, directories, ticket inventories, etc.

Uses- Data Analytics for E-commerce, Business Intelligence, Market Research, Sentiment Analysis

Conclusion

Quite obviously you need both such extractors handy to take care of various use cases. The only way generic extractors can work for detailed datasets is if everyone employs standard data formats on the web (Read our post on standard data formats here). However, given the internet penetration to the masses and the variety of things folks like to do on the web, this is being overly futuristic.

So while site-specific extractors are going to be around for quite some time, the challenge now is to tweak the generic ones to work better. At PromptCloud, we have added ML components to make them smarter and they have been working well for us so far.

What have your challenges been? Do drop in your comments.

Source: https://www.promptcloud.com/blog/scraping-data-site-specific-extractors-vs-generic-extractors/

How to scrape Amazon with WebDriver in Java

Here is a real-world example of using Selenium WebDriver for scraping.
This short program is written in Java and scrapes book title and author from the Amazon webstore.
This code scrapes only one page, but you can easily make it scraping all the pages by adding a couple of lines.

You can download the souce here.

import java.io.*;
import java.util.*;
import java.util.regex.*;

import org.openqa.selenium.*;
import org.openqa.selenium.firefox.FirefoxDriver;

public class FetchAllBooks {

    public static void main(String[] args) throws IOException {

        WebDriver driver = new FirefoxDriver();
      

driver.navigate().to("http://www.amazon.com/tag/center%20right?ref_=tag_dpp_cust_itdp_s_t&sto

re=1");

        List<WebElement> allAuthors =  driver.findElements(By.className("tgProductAuthor"));
        List<WebElement> allTitles =  driver.findElements(By.className("tgProductTitleText"));
        int i=0;
        String fileText = "";

        for (WebElement author : allAuthors){
            String authorName = author.getText();
            String Url = (String)((JavascriptExecutor)driver).executeScript("return

arguments[0].innerHTML;", allTitles.get(i++));
            final Pattern pattern = Pattern.compile("title=(.+?)>");
            final Matcher matcher = pattern.matcher(Url);
            matcher.find();
            String title = matcher.group(1);
            fileText = fileText+authorName+","+title+"\n";
        }

        Writer writer = new BufferedWriter(new OutputStreamWriter(new

FileOutputStream("books.csv"), "utf-8"));
        writer.write(fileText);
        writer.close();

        driver.close();
    }
}

Source: http://scraping.pro/scraping-amazon-webdriver-java/

Web Scraping: Business Intelligence

Web scraping is simply getting of information that is both hidden and unhidden from the internet. Web scraping is one of the latest technologies used in harvesting data from WebPages. It has been used to extract useful information for practical and beneficial applications and its interpretation has been tested in decision making. Web scraping is a new term that overshadows the traditional data harvesting technique that was used before. It has been regarded as knowledge discovery in databases for research and even marketing monitoring.

This article explores the various business intelligence ways in which web scraping can be used to be of importance.

Web scraping services has been used by many companies that have a strong customer focus. These companies range from sectors like retail, financial services, and marketing and communication organizations. It quite important to realize that web scraping has great signifies and impact in the varied commercial applications for the better understanding and prediction of the critical data. The data may range from stocks to consumer behaviors. The consumer behaviors are better shown in trends like customer profiles, purchasing and industry analysis among others.

Source:http://www.loginworks.com/blogs/web-scraping-blogs/web-scraping-business-intelligence/

Web Scraping: The Invaluable Decision Making Tool

Business decisions are mandatory in any company. They reflect and directly influence about the future of the company. It is important to realize that decisions must be made in any business situation. The generation of new ideas calls for new actions. This in turn calls for decisions. Decisions can only be made when there is adequate information or data regarding the problem and the cause of action to be taken. Web scraping offers the best opportunity in getting the required information that will enable the management make a wise and sound decision.

Therefore web scraping is an important part in generation of the practical interpretations for the business decision making process. Since businesses take many courses of actions the following areas call for adequate web scraping in order to make outstanding decisions.

1. Suppliers. Whether you are running an offline business there is need to get information regarding your suppliers. In this case there are two situations. The first situation is about your current suppliers and the second situation is about the possibility of acquiring new suppliers. By web scraping you has the opportunity to gather about your suppliers. You need to know other business they are supplying to and the kind of discounts and prices they offer to them. Another important aspect about consumers is to determine the periods when they have surplus and therefore be able to determine the purchasing prices.

Web scraping can provide new information concerning new suppliers. This will make a cutting edge in the purchasing sector. You can get new suppliers that have reasonable prices. This will go a long way in ensuring a profitable business. Therefore web scraping is an integral process that should be taken first before making a vital decision concerning suppliers.

Source:http://www.loginworks.com/blogs/web-scraping-blogs/web-scraping-invaluable-decision-making-tool/