Big Data Process and Analysis in R
I know this is not a new concept by any stretch in R, and I have browsed the High Performance and Parallel Computing Task View. With that said, I am asking this question from a point of ignorance as I have no formal training in Computer Science and am entirely self taught.
Recently I collected data from the Twitter Streaming API and currently the raw JSON sits in a 10 GB text file. I know there have been great strides in adapting R to handle big data, so how would you go about this problem? Here are just a handful of the tasks that I am looking to do:
- Read and process the data into a data frame
- Basic descriptive analysis, including text mining (frequent terms, etc.)
Is it possible to use R entirely for this, or will I have to write some Python to parse the data and throw it into a database in order to take random samples small enough to fit into R.
Simply, any tips or pointers that you can provide will be greatly appreciated. Again, I won't take offense if you describe solutions at a 3rd grade level either.
Thanks in advance.
If you need to operate on the entire 10GB file at once, then I second @Chase's point about getting a larger, possibly cloud-based computer.
(The Twitter streaming API returns a pretty rich object: a single 140-character tweet could weigh a couple kb of data. You might reduce memory overhead if you preprocess the data outside of R to extract only the content you need, such as author name and tweet text.)
On the other hand, if your analysis is amenable to segmenting the data -- for example, you want to first group the tweets by author, date/time, etc -- you could consider using Hadoop to drive R.
Granted, Hadoop will incur some overhead (both cluster setup and learning about the underlying MapReduce model); but if you plan to do a lot of big-data work, you probably want Hadoop in your toolbox anyway.
A couple of pointers:
an example in chapter 7 of Parallel R shows how to setup R and Hadoop for large-scale tweet analysis. The example uses the RHIPE package, but the concepts apply to any Hadoop/MapReduce work.
you can also get a Hadoop cluster via AWS/EC2. Check out Elastic MapReduce for an on-demand cluster, or use Whirr if you need more control over your Hadoop deployment.