Page Rankings: What do they
teach us?
Faina Linkov, PhD
Ronald LaPorte, PhD
And the Global Health Network Supercourse project
University of Pittsburgh
Google’s description of page rank
…PageRank relies on the uniquely democratic
nature of the web by using its vast link structure
as an indicator of an individual page's value. In
essence, Google interprets a link from page A to
page B as a vote, by page A, for page B. But,
Google looks at more than the sheer volume of
votes, or links a page receives; it also analyzes
the page that casts the vote. Votes cast by
pages that are themselves "important" weigh
more heavily and help to make other pages
"important…"
Understanding Page Rank
• All search engines assign a value to your
site based on inbound links
• Google calls this relevancy factor “Page
Rank” (PR) - synonymous with popularity
ranking
• An inbound link is a vote for your page
• An outbound link is a vote for the page
you’re linking to
Understanding Page Rank
•
•
•
A page is assigned PR as soon as it’s
indexed
The page receiving the most inbound
links gets the highest page rank
You can pass PR around to pages on
your site
Outbound Links
• Your popularity is not determined by the
sites you link to
• Your outbound links affect the popularity of
the sites you’re linking to
• Internal links and inbound links have the
most impact on your popularity
• Outbound links help identify you with a
hub
Page Rankings and the
Supercourse
Supercourse Model: lecture sharing
Teacher in
Mexico
Teacher in
Bolivia
Teacher in
Havana
Teacher in
Santo
Domingo
Teacher in
Pittsburgh
Teacher in San
Francisco
Current Status
40000 participants
(15 Nobel Prize winners)
151 countries
Over 2800 lectures
A Model for
Developing and Prescribing
Assistive Technology Devices
Mary Ellen Buning, PhD, OTR/L,
ATP
Jue Wang, PhD
University of Pittsburgh
Cardiovascular Epidemiology:
Definitions
Historical Perspectives and
Assessing Risk of CVD
Recent trends and population
differences in CHD and CHD risk
factors
Nathan Wong
Topic – Google PPT. lecture ranking for the Supercourse
Amebiasis - 2(English) 3 (Spanish)
Communicable Disease and disasters - 3/372
Cardiovascular epidemiology
- 1&2/9730
Diabetes epidemiology - 3/13,000
Evidenced based public health - 1/158
Global Health - 1&2/3,820,000
Indian Health - 1&2/56,000
Infectious disease epidemiology - 1/21,000
Islamic/Arab health - 2/537
Information on the Web - 1/78
Meta Analysis - 6/116,000
Occupation Cancer - 3/18,000
Pakistani Health - 6&7/18,500
Pitt.edu - 2/2,400,000
Primordial Prevention - 1/126
Russian health - 2&3/19,000
Tsunami - 11/31,000
Health (this is a search on the whole web for the term "health" (985,000,000 pages)
NIH =
3
WHO =
40
CDC = 220
PAHO= 224
Global health (328,000,000 pages)
US AID
3
Gates
4
Supercourse
8
CDC
12
WHO
67
NIH
70
PAHO
>300
Page Rankings within NIH search term, overall , and then only for the Institutes
All
NLM
NCCAM
NIMH
NHLBI
CIT
CSR
NIAID
NEI
NICHD
NIAMS
NIDA
NIA
NIDDK
NINDS
NIAAA
CC
NIEHS
NIDCD
NCRR
NINR
NIBIB
NCI
FIC
NIGRI
NIGMS
NCMHD
3
13
12
19
27
29
30
36
42
48
56
59
62
66
69
73
75
82
133
205
221
236
>300
>300
>300
>300
Only Institutes
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
Conclusions
• Page ranking is an important tool helping
to assess the popularity and the quality of
the website
• Supercourse lectures are scored very
highly by Google rankings
• We need to explore how page rankings
can influence information dissemination in
the US and worldwide