Why is a Web scraping service better than Scraping tools

Why is a Web scraping service better than Scraping tools

Web scraping has been making ripples across various industries in the last few years. Newer businesses can employ web scraping to gain quick market insights and equip themselves to take on their competitors. This works like clockwork if you know how to do the analysis right. Before we jump into that, there is the technical aspect of web scraping. Should your company use a scraping tool to get the required data from the web? Although this sounds like an easy solution, there is more to it than what meets the eye. We explain why it’s better to go with a dedicated web scraping service to cover your data acquisition needs rather than going by the scraping tool route.

Cost is lowered

Although this might come as a surprise, the cost of getting data from employing a data scraping tool along with an IT personnel who can get it done would exceed the cost of a good subscription based web scraping service. Not every company has the necessary resources needed to run web scraping in-house. By depending on a Data service provider, you will save the cost of software, resources and labour required to run web crawling in the firm. Besides, you will also end up having more time and less worries. More of your time and effort can therefore go into the analysis part which is crucial to you as a business owner.

Accessibility is high with a service

Multifaceted websites make it difficult for the scraping tools to extract data. A good web scraping service on the other hand can easily deal with bottlenecks in the scraping process when it may arise. Websites to be scraped often undergo changes in their structure which calls for modification of the crawler accordingly. Unlike a scraping tool, a dedicated service will be able to extract data from complex sites that use Ajax, Javascript and the like. By going with a subscription based service, you are doing yourself the favour of not being involved in this constant headache.

Accuracy in results

A DIY scraping tool might be able to get you data, but the accuracy and relevance of the acquired data will vary. You might be able to get it right with a particular website, but that might not be the case with another. This gives uncertainty to the results of your data acquisition and could even be disastrous for your business. On the other hand, a good scraping service will give you highly refined data which is in a ready to consume form.

Outcomes are instant with a service

Considering the high resource requirements of the web scraping process, your scraping tool is likely to be much slower than a reputed service that has got the right infrastructure and resources to scrape data from the web efficiently. It might not be feasible for your firm to acquire and manage the same setup since that could affect the focus of your business.

Tidying up of Data is an exhausting process

Web scrapers collect data into a dump file which would be huge in size. You will have to do a lot of tidying up in this to get data in a usable format. With the scraping tools route, you would be looking for more tools to clean up the data collected. This is a waste of time and effort that you could use in much better aspects of your business. Whereas with a web scraping service, you won’t have to worry about cleaning up of the data as it comes with the service. You get the data in a plug and use format which gives you more time to do better things.

Many sites have policies for data scraping

Sometimes, websites that you want to scrape data from might have policies discouraging the act. You wouldn’t want to act against their policies being ignorant of their existence and get into legal trouble. With a web scraping service, you don’t have to worry about these. A well-established data scraping provider will definitely follow the rules and policies set by the website. This would mean you can be relieved of such worries and go ahead with finding trends and ideas from the data that they provide.

More time to analyse the data

This is so far the best advantage of going with a scraping service rather than a tool. Since all the things related to data acquisition is dealt by the scraping service provider, you would have more time for analysing and deriving useful business decisions from this data. Being the business owner, analysing the data with care should be your highest priority. Since using a scraping tool to acquire data will cost you more time and effort, the analysis part is definitely going to suffer which defies your whole purpose.

Bottom line

It is up to you to choose between a web scraping tool and a dedicated scraping service. Being the business owner, it i s much better for you to stay away from the technical aspects of web scraping and focus on deriving a better business strategy from the data. When you have made up your mind to go with a data scraping service, it is important to choose the right web scraping service for maximum benefits.

Source: https://www.promptcloud.com/blog/web-scraping-services-better-than-scraping-tools

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

Difference between Data Mining and KDD

Difference between Data Mining and KDD

Data, in its raw form, is just a collection of things, where little information might be derived. Together with the development of information discovery methods(Data Mining and KDD), the value of the info is significantly improved.

Data mining is one among the steps of Knowledge Discovery in Databases(KDD) as can be shown by the image below.KDD is a multi-step process that encourages the conversion of data to useful information. Data mining is the pattern extraction phase of KDD. Data mining can take on several types, the option influenced by the desired outcomes.

Knowledge Discovery in Databases Steps
Data Selection

KDD isn’t prepared without human interaction. The choice of subset and the data set requires knowledge of the domain from which the data is to be taken. Removing non-related information elements from the dataset reduces the search space during the data mining phase of KDD. The sample size and structure are established during this point, if the dataset can be assessed employing a testing of the info.
Pre-processing

Databases do contain incorrect or missing data. During the pre-processing phase, the information is cleaned. This warrants the removal of “outliers”, if appropriate; choosing approaches for handling missing data fields; accounting for time sequence information, and applicable normalization of data.
Transformation

Within the transformation phase attempts to reduce the variety of data elements can be assessed while preserving the quality of the info. During this stage, information is organized, changed in one type to some other (i.e. changing nominal to numeric) and new or “derived” attributes are defined.
Data mining

Now the info is subjected to one or several data-mining methods such as regression, group, or clustering. The information mining part of KDD usually requires repeated iterative application of particular data mining methods. Different data-mining techniques or models can be used depending on the expected outcome.
Evaluation

The final step is documentation and interpretation of the outcomes from the previous steps. Steps during this period might consist of returning to a previous step up the KDD approach to help refine the acquired knowledge, or converting the knowledge in to a form clear for the user.In this stage the extracted data patterns are visualized for further reviews.
Conclusion

Data mining is a very crucial step of the KDD process.

For further reading aboud KDD and data mining ,please check this link.

Source: http://nocodewebscraping.com/difference-data-mining-kdd/

Invest in Data Extraction to Grow Your Business

Invest in Data Extraction to Grow Your Business

Automating your employees’ processes can help you increase productivity while keeping the cost of used resources at a minimum. This can help you focus your time and money in much needed areas of your company so that you can thrive in your industry. Data extraction can help you achieve automation by targeting online data sources (websites, blogs, forums, etc) for information and data that can be useful to your business. By using software rather than your employees, you can oftentimes get more accurate data and more thorough information that people may miss. The software can handle the volume that you need and will deliver the results that you desire to help your company.
See the Power of Data Extraction Online

To see all of the ways that data extraction tools and software can benefit your business, There you can read about the features of the software, practical uses for businesses and also schedule a demo before you buy.

Source: http://www.connotate.com/invest-in-data-extraction-to-grow-your-business/

Best Alternative For Linkedin Data Scraping

Best Alternative For Linkedin Data Scraping

When I started my career in sales, one of the things that my VP of sales told me is that ” In sales, assumptions are the mother of all f**k ups “. I know the F word sounds a bit inappropriate, but that is the exact word he used. He was trying to convey the simple point that every prospect is different, so don’t guess, use data to come up with decisions.

I joined Datahut and we are working on a product that helps sales people. I thought I should discuss it with you guys and take your feedback.

Let me tell you how the idea evolved itself. At Datahut, we get to hear a lot of problems customers want to solve. Almost 30 percent of all the inbound leads ask us to help them with lead generation.

Most of them simply ask, “Can you scrape Linkedin for me”?

Every time, we politely refused.

But not anymore, we figured out a way to solve their problem without scraping Linkedin.

This should raise some questions in your mind.

1) What problem is he trying to solve?– Most of the time their sales team does not have the accurate data about the prospects. This leads to a total chaos. It will end up in a waste of both time and money by selling the leads that are not sales qualified.

2) Why do they need data specifically from Linkedin? – LinkedIn is the world’s largest business network. In his view, there is no better place to find leads for his business than Linkedin. It is right in a way.

3) Ok, then what is wrong in scraping Linkedin? – Scraping Linkedin is against its terms and it can lead to legal issues. Linkedin has an excellent anti-scraping mechanism which can make the scraping costly.

4) How severe is the problem? – The problem has a direct impact on the revenues as the productivity of the sales team is too low. Without enough sales, the company is a joke.

5) Is there a better way? – Of course yes. The people with profiles in LinkedIn are in other sites too. eg. Google plus, CrunchBase etc. If we can mine and correlate the data, we can generate leads with rich information. It will have better quality than scraping LinkedIn.

6) What to do when the machine intelligence fails? – We have to use human intelligence. Period!

Datahut is working on a platform that can help you get leads that match your ideal buyer persona. It will be a complete Business intelligence platform powered by machine and human intelligence for an efficient lead research & discovery.We named it Leadintel. We’ve also established some partnerships that help to enrich the data and saves the trouble of lawsuits.

We are opening our platform for beta users. You can request an invitation using the contact form. What do you think about this? What are your suggestions?

Thanks for reading this blog post. Datahut offers affordable data extraction services (DaaS) . If you need help with your web scraping projects let us know and we will be glad to help.

Source:http://blog.datahut.co/best-alternative-for-linkedin-data-scraping/