Telecon With LANL

Date: Wednesday, 27 May, 2015

One Million DMOZ Sample URI Profiling

The list of one million sample URIs from DMOZ used in this analysis is available here.

Relative Cost

For a given pair of an archive and a profiling policy, number of unique keys generated determines the cost of the profile for the archive. If the cost of the complete knowledge profile URIR is considered to be 1 in which the number of keys in it equal to the number of unique URI-Rs in the archive, then relative cost of other profiles can be calculated as follows:

Relative Cost (profile, archive) = No. of keys in the given profile for the archive / No. of keys in URIR profile for the archive

Search Precision

For a given pair of an archive and a profile, and a set of sample lookup URIs, accuracy of predicting the absence or presence of the sample URIs in the archive using the profile determines the precision of the profile for the archive. If the search precision of the complete knowledge profile URIR is considered to be 1 which can predict the presence or absence with 100% accuracy, then search precision of other profiles can be calculated as follows:

Search Precision (profile, archive, sample) = No. of correctly predicted URIs from the sample / No. of all the predicted URIs

In our case so far there are no false negatives hence the formula above is simple. It will change slightly when there will be chances of getting some false negatives as well.

Sample Intermediate Values

Sample URI: https://www.news.BBC.co.uk/Images/Logo.png?width=200&height=80&rotate=90#fragment
Canonical URL: news.bbc.co.uk/Images/Logo.png?height=80&rotate=90&width=200
SURT: uk,co,bbc,news)/Images/Logo.png?height=80&rotate=90&width=200
Registered Domain: uk,co,bbc)/
Subdomain Count: 1
Path Count: 2
Query Count: 3
PathQuery Count: 2 + 3 = 5
Path Initial: I
Path Initial (tight): i

Cost Precision Table

Policy	Example	ArchiveIt			UKWA
Policy	Example	Keys (Cost)	Existence Prediction (Out of 1M DMOZ Sample URIs)	Precision	Keys (Cost)	Existence Prediction (Out of 1M DMOZ Sample URIs)	Precision
H1P0	uk)/	282	999,912	0.041	162	996,311	0.019
onlydom	uk,co,bbc)/	2,086,552	507,017	0.081	2,011,203	352,347	0.054
tillsubdom	uk,co,bbc)/1	2,199,576	497,847	0.082	2,080,278	335,301	0.057
H3P0	uk,co,bbc)/	3,049,211	445,886	0.092	2,034,487	281,505	0.068
tillpath	uk,co,bbc)/1/2	4,681,511	467,861	0.088	4,056,659	260,112	0.074
pathquery*	uk,co,bbc)/1/5	4,966,968	464,631	0.088	4,437,415	251,766	0.076
tillquery	uk,co,bbc)/1/2/3	5,607,513	457,586	0.090	5,087,497	245,101	0.078
pathquerysuppinit**	uk,co,bbc)/1/5/i	10,381,970	349,678	0.117	18,481,581	180,518	0.106
tillinit	uk,co,bbc)/1/2/3/I	11,247,577	343,620	0.119	19,332,428	175,530	0.109
HxP1	uk,co,bbc,news)/Images	84,720,364	233,825	0.175	91,433,257	110,177	0.174
URIR	uk,co,bbc,news)/Images/Logo.png?height=80&rotate=90&width=200	1,873,600,422	# 40,969	1.000	673,796,541	# 19,121	1.000

Notes

# No false positives.
* pathquery policy is similar to the "no first char" summarization of LANL.
** pathquerysuppinit policy is similar to the "with first char" summarization of LANL.
H1P0 is TLD-only profile, URIR is complete knowledge profile, H3P0 is a profile with three segments from host and no segments from the path, and HxP1 is a profile with all the host segments and one path segment.

Analysis

Following two figures show the search precision of each profile listed in the above table for the two archives Archive-It and UK Web Archive respectively. (The URIR/Complete Knowledge profile has search precision 1.)

The search precision values illustrated above can bee seen on the relative cost scale below. (The URIR/Complete Knowledge profile has Cost 1.)

The cost and precision values can be seen in perspective of the complete knowledge profile below.