CPSFS: A Credible Personalized Spam Filtering Scheme by Crowdsourcing

Algorithm 1

Local spam filtering algorithm.

Input:

: local spam list

: an email set from inbox

: local trust-similarity list

Output:

: updated spam list

Let is the th email of , is the th item of , is th contact’s trust,

is th contact’s similarity, is the trust of the sender of , is the number of

emails, is the number of items in , is the number of contacts, is the

generated spam report, : trust threshold, : interest similarity threshold, flag is

the subject of email

for to do

if flag = “spam report”

if

content of the email

for to do

if

forwarding to contact

end if

end for

end if

else

hash// Calculating MD5 hash for

for to do

if

put into junk box

end if

end for

generating the spam report of

for to do

if

sending to contact

end if

end for

end for

return