Sunday, November 6, 2011

Current cumulatives

Folks:

 I am attaching the current cumulatives. I scaled the homework1 to 5points homework 2 to 6pt each, the google paper to 2pt--so a total of 11pt, the midterm to 20pt, the pop quiz to 2pt,
the projects to 10pt--thus a total of 44pt. 

The extra credit points are kept separate from the main cumulative.

If you see any entry errors, please let us know.

Rao

Friday, November 4, 2011

Google's Timelier Search Results

Google has tweaked its search algorithm to present results which are as recent as possible for a particular query. You can read more about this here http://www.informationweek.com/news/development/web/231902412

Preethi

Social networks lectures..

Folks:

 Because I decided to add lecture topics on Map-reduce and search advertising, I will have to skip one of the topics I normally cover. I reluctantly decided that it would be "Social Networks"--mostly because it is a self-contained 2-class topic for which video lectures from a previous offering are available (see below).

In addition to being quite engaging, this topic also comes bundled with a discussion on power laws and their importance. 

I would encourage you to watch the video lectures. I will also give optional homework questions on the topic. If you choose to do them, you can get extra credit.

Rao





===========
Social networks and their applications on the Web
  • L14 Audio of [March 5, 2010] (Video of the lecture video part 1 (the first 1hr 5min 4gb) and video part 2 (the remaining 10+ min) Efficient computation of pagerank (and how it is important to not represent the M* matrix explicitly given that it is not sparse); doing block-based pagerank iteration to avoid thrashing, the use of asynchronous pagerank iteration to improve convergence. 
    [starts at 25min] Social networks start. Connections between link-analysis and the general field of social network analysis. Some iconic examples of social network analysis (Typhoid Mary, Patient Zero, Web graph (and its small-world nature), Offcial florida ballot viral spread, Saddam capture, Aardvark acquisition). Applications of social networks. Graph-based representation and analysis of social entworks. Measures of influence and centrality. Smallworld phenomena--and their examples in kevin bacon game and erdos number.
  • L15 Audio of [March 9, 2010] (Video of the lecture video part 1 (the first 1hr 5min 4gb) and video part 2 (the remaining 10+ min) Milgram experiment; six-degrees of separation; (uniform) random networks and their properties; realizing that the small world probability increases sharply to 1 right near k=1; where k is the average (expected) degree of the random network. If human networks are (uniform) random, then they will have small-world phenomena (since k, i.e., average number of friends per person, is almost always greater than 1). Trying to confirm whether large-scale social networks are in fact uniform random by comparing their degree distribution to the Poisson degree distribution expected for random networks. Realizing that most real world network degree distributions instead correspond to negative sloping straightlines in log-log space (which means they are of the form P=1/k^r, which is called powerlaws. Discussion of the properties of power-law disributions (which have long tails that fall off only polynomially rather than exponentially). Implications of long tails on everything from probability of existence of such highly-linked sites as google to the ability of making money selling west wing DVDs and iranian classical music CDs on the web. Discussion of generative models which can result in power law distributions over network degrees.
  • L16 Audio of [March 11, 2010] (Video of the lecture video part 1 (the first 1hr; battery died after that :( ) Attacks vs. disruptions on powerlaw vs. exponential networks; navigation on social networks; applications of social networks; discussion of trust and reputation; trust rank (a page-rank variant); discussion of social search (and aardvark); discussion of othe powerlaws in cse494--zipf's law; heap's law (and even benford's law).

Tuesday, November 1, 2011

Bi-annual Grade Anxiety Amelioration Program

Folks

 I have been meaning to send this mail earlier than the course withdrawal deadline, but got side-tracked into various deadlines. Better late than never.. 

I wanted to reiterate something I had said at the beginning of the semester about letter grades in this course. 

As I said, I don't go with 95-->A+; 90-->A  sort of scale. So, you shouldn't worry too much based just on your
cumulatives. 

I also recognize that people who can't keep up with the demands of the course leave early on (or don't register to begin with--thanks to the miracle of internet-word-of-mouth)--thus I normally don't have the
same kind of bottom distribution as might be present in other classes. 

My general advice to anyone who has come up to this point in the course and has done all assignments, and is enjoying the 
course, is to de-stress (note the "de" not "di") and continue (unless you need absolute guarantee of an A+). Your personal mileage of course may vary.

Rao


ps: If it helps, here are the final cumulatives and the actual reported grades for a previous offering of this course. The first 
three are 471 and the rest are 598. This is for illustrative purposes.
 There are *no* implicit guarantees that if you get those points, you will get those grades. If you have other questions, feel free to 
send me email.





 
88.40A+
79.57A
62.83B

 
91.97A+
90.61A+
87.55A+
85.76A
85.11A
84.34A
84.00A
83.88A
83.85A
81.27A-
79.92B+
78.76B+
78.63B+
74.76B
69.64B
69.35B

You might want to read this easy to read paper on Netflix prize before next class...

http://rakaposhi.eas.asu.edu/cse494/lsi-for-collab-filtering.pdf

it is in the readings and tells you how collaborative filtering and LSI style techniques are combined. We will talk only briefly about it next class

rao

office hours cancelled (again!)

Folks

 Due to a conflict I can't hold office hours today. If you were planning to meet with me, you can talk to me anytime tomorrow morning.

sorry
rao