Posts Tagged ‘ merge ’

Identifying Records in Data Frame A That Are Not Contained In Data Frame B – A Comparison

October 12, 2011
By
Identifying Records in Data Frame A That Are Not Contained In Data Frame B – A Comparison

Yesterday I launched my first question at Stackoverflow and apparently did a lot of things wrong as I managed to get my question closed wihtin hours http://stackoverflow.com/questions/7728462/identify-records-in-data-frame-a-not-contained-in-data-frame-b I had collected 9 different solutions to the problem and made the mistake to put it all within the original question space. So people complained and told me … Continue reading...

Read more »

Merging Two Different Datasets Containing a Common Column With R and R-Studio

August 2, 2011
By
Merging Two Different Datasets Containing a Common Column With R and R-Studio

Another way for the database challenged (such as myself!) for merging two datasets that share at least one common column… This recipe using the cross-platform stats analysis package, R. I use R via the R-Studio client, which provides an IDE wrapper around the R environment. So for example, here’s how to merge a couple of

Read more »

Summarize Data by Several Variables

May 23, 2011
By
Summarize Data by Several Variables

Here's an example how to conveniently summarize data with the cast function (package reshape). By the way you see how this could be done "in-conveniently" by hand. You also see how a for-loop works and how a matrix is constructed and fill...

Read more »

Example 8.33: Merging data sets one-to-many

April 5, 2011
By
Example 8.33: Merging data sets one-to-many

It's often necessary to combine data from two data sets for further analysis. Such merging can be one-to-one, many-to-one, and many-to-many. The most common form is the one-to-one match, which we cover in section 1.5.7. Today we look at a one-to-man...

Read more »

Example 8.18: A Monte Carlo experiment

December 13, 2010
By
Example 8.18: A Monte Carlo experiment

In recent weeks, we've explored methods to fit logistic regression models when a state of quasi-complete separation exists. We considered Firth's penalized likelihood approach, exact logistic regression, and Bayesian models using Markov chain Monte Ca...

Read more »

R: Zip fastener for two data frames / combining rows or columns of two dataframes in an alternating manner

March 27, 2009
By
R: Zip fastener for two data frames / combining rows or columns of two dataframes in an alternating manner

Sometimes I find it useful to merge two data frames like the following ones   X1 X2 X3 X4 Y1 Y2 Y3 Y4 1  o  o  o  o X X X X 2  o  o  o  o X X X X 3  o  o  o  o X X X X by using zip feeding either

Read more »