Tag Archives: beijing

to be an eBay seller...and explore the social network effect

It is interesting to work for eBay; however, most of the time I am looking at the massive data without really thinking about how they are generated... for instance, I have no idea how difficult it should be to be a successful seller on eBay. It somehow sounds a little wired that we talk about mechanism design (say, whether eBay's ecological system is better than Taobao's) without personal experience.

To step in, I should try - and there was a precious opportunity for me to do so! After the China-R conference in Beijing, two professors from Australia (Graham Williams and John Maindonald) asked if they could buy additional packs of the playing cards somewhere so they could share with their colleagues and friends. Then why not on eBay?

Then I typed "ebay.com" in my browser... log in...sell...The photos were prepared several months before... upload... done!

However, when I was trying to copy the link...it was so long!


Then I noticed the lovely "share to twitter" button on the left ^O^ Let me just use this one!

A simple click leads to a new tweet... of course I need to at some useR... Yihui should be the best choice 😛

Not sure what has happened during the night... when I wake up next morning, they are almost sold out (I listed 10!). Well... then the painful shipping process comes. Thanks to the fantastic e-packet tool(http://shippingtool.ebay.cn), it was pretty convenient to complete shipping online. OK, the postman will take care of them. Goodbye, my cards...

The special benefit is that now I realize how powerful the social network could be. Without spreading information through twitter, it would be much slower if we manually copy and paste the URL in emails. Social network sites control it just in the right way - "word of month" helps customer selects goods based on their reliable information source. Some comments:

Karthik Ram@_inundata 30 May

Totally bizarre #rstats playing cards for sale on @ebay. http://bit.ly/18BmwTg 

Geoff J@geoffjentry 30 May

@_inundata I once bought a "used wife" on @ebay yet somehow this is odder.

Ok...is it that wired?

BTW, the integration of eBay site and twitter is pretty good. Once the link is attached the listing image also appears. See below.2013-06-04 14_11_43-Karthik Ram (_inundata) on Twitter

[Conference Report] A First Course on Statistical Thinking II: Common Flaws in News Reports

Long time no update...I should apologize for this.

magic letters

This post is about the conference report I presented last month (26th, May) in the 5th China-R Conference at Renmin University of China, Beijing.

The talk contains several intuitive examples about the misuse of numbers in news reports. Basic statistics knowledge is not hard to learn, but pretty easy to forget. In the slides, I picked some popular pieces of news which mislead the public intentionally. I aimed at telling people how to keep a clear mind - consequently you will be able to distinguish between tricks and real statistical models.

The incentive for me to deliver a presentation like this is to show students how interesting statistics could be, therefore hopefully some of them will grow more interests in this subject and hence go further in their studies. Knowledge is always easy to learn and hard to apply - but without applications, what's the point of studying? Why are you paying much a great cost (of time) on studying in school?

The original slides can be found here: http://cos.name/wp-content/uploads/2012/05/8-chenliyun-rumor.zip (in Chinese).

An easier version of this topic was presented earlier at a popular science training lecture hosted by Songshuhui.net, an NGO in China works on popular science. The full record in Chinese can be visited on their website: http://s-camp.songshuhui.net/events/s-workshop/class008_part-1/

A speech on econometrics and R

From next week I'll go to Beijing and Shanghai respectively to give a speech on R. Yesterday I just finished the beamer for presentation in English. Not very long, because I'm afraid of making any serious mistakes.

Here I would like to list the outline.


From Economics to R --Using R in Economics and Econometrics

(At first it was "Using R in Economics, Statistics and Econometrics". However, I think it is no good to mention "statistics" since I'm not professional in that area. The same to "economic statistics". Therefore I only mention economics and econometrics instead eventually.)


1 Economics and Statistics

  • The Irreplaceable Support
  • Software about econometrics

2 Main Econometric Methods

  • Similar to statistics
  • Realization in R

3 Now Work with R!

  • Transfer the Data
  • Cooperate with LATEX
  • My own experience

Maybe the outline is a little too simple, but in fact I don't have too much to talk, since I'm a beginner of economics and R myself. I really appreciate the opportunity to give a speech on the 2nd Chinese R Conference, and I do hope that there will all right. Anyway, I have no better choice but do my best.

A more detailed post may appear after the lecture.

[2010.02. 20 Updated]