The New York Times: By NEIL MacFARQUHAR
CAMBRIDGE, Mass. — Troll through the Iranian blogosphere and you can find all manner of unexpectedly harsh critiques denouncing the government of the Islamic Republic, from reformists who revile it as well as conservatives who support it.

One conservative blogger deplored the rampant inflation undermining the middle class, saying it forced girls into prostitution to support their families. Others identified themselves as fans of President Mahmoud Ahmadinejad, yet they condemned government corruption and what they called arbitrary arrests. A fourth declared that government statistics were a lot of nonsense.

What gets filtered out is not entirely predictable either. Even some religious topics are deemed unacceptable. The government blocked the site of a blogger advocating the Shiite Muslim custom of temporary marriage, which is legal and considered a way for the young to relieve their sexual frustration without breaking religious laws.

Over all, a new study by the Berkman Center for Internet and Society at Harvard Law School shows that Iran’s blogosphere mirrors the erratic, fickle and often startling qualities of life in the Islamic republic itself. The rules of what is permissible fluctuate with maddening imprecision, so people test the limits.

Like women who inch their head scarves back to see how much hair they can show or people who flout the ban on alcohol by drinking at home, bloggers seem to be testing just how far they can push. And, like Iran’s other rule breakers, some pay a price.

In 2004, according to Human Rights Watch, 21 bloggers or people who worked at Internet news sites critical of the government were arrested, and some of them were tortured. Periodic arrests since then have ended with jail terms.

The study, conducted over the last year by the Berkman Center, was financed by the State Department and is part of a larger and longer project on the impact new communications media are having on democracy and democratization in several countries. The research being released Sunday documents what types of blogs are being posted in Iran.

Researchers used computer software to analyze more than 6,000 blogs by subject matter to get a general sense of what issues Iranians were discussing; then the team, which included Persian-speaking students, read more than 500 of the postings.

To build a fuller picture of the Iranian blogosphere, the researchers also used the results of a parallel study that documents what blogs were being blocked by the authorities in 60 countries, including Iran. That study is also being done at the Berkman Center in collaboration with universities in Canada and Britain.

The researchers’ general conclusion was that, “despite periodic persecution,” many Iranians are able to use blogs to express “viewpoints challenging the ruling ideology of the Islamic Republic.”

The study found, for instance, that fewer than a quarter of blogs pushing for change, including those written by expatriates, were blocked. In addition, conservatives of all stripes maintain a lively debate about President Ahmadinejad.

“Arguing about stuff, arguing about public affairs, is taking root in the blogosphere on the conservative side, on the reformist side, all over,” said John Kelly, the founder of Morningside Analytics, a New York company that took part in the study and created the software that helped researchers group blogs together by subject and social networks.

“We don’t know if the government is not trying or not able to block as much as we thought,” said Mr. Kelly, who wrote the study with Bruce Etling, the director of the project at Berkman. “They may allow a certain amount of online discourse to be there because it seems to underline the legitimacy of the system.”

Political groups bash each other with gusto from both sides of the political divide. One conservative blogger mocked reformists for pretending to care about economic matters. “The nature of the reformists is actually extremism,” wrote a blogger under the name Shahrahedalat or the Highway of Justice, adding that the Iranian people would not be deceived.

Reformist supporters give back as good as they get. Even if supporting reformist politicians is nearly futile, wrote a blogger under the name Inharfha or These Talks, it is “much better that sitting back and watching how our country is being taken back to the ruins of Medieval times.”

Iran seems to handpick which blogs it blocks, but researchers admit that Iran’s filtering policy and techniques remain opaque.

“Our sense is that the government in Iran doesn’t see the blogosphere as bad as a whole,” Mr. Kelly said, noting that Iranian exiles have alleged that the government organizes and pays bloggers to put out the party line. “What they are trying to do is to promote more young religious voices, to pile as many conservatives into the network as they can.”

Researchers said many of the religious sites they found used the same artwork and linked to one another. During last month’s parliamentary elections, for example, many religious blogs displayed a banner encouraging Iranians to vote and a picture of President Ahmadinejad.

Blocked blogs discussed topics as varied as erotic poetry and computer coding. The blog of an Iranian woman who wrote about the joys of working in a relaxed, nonsegregated environment with men was blocked, as was that of a poet who used curse words.

The map of the Iranian blogosphere that the Internet and Democracy Project produced (available Sunday at cyber.law.harvard.edu/publications/2008/Mapping_Irans_Online_Public) resembles the night sky, with each dot representing one blog and the main constellations indicating groups of blogs that share common interests and attitudes.

Sprays of yellow and green represent secular/reformist blogs. More women and expatriates appear here than anywhere else. The points colored red, turquoise and orange show all the blogs on the religious/conservative pole.

The study found that the next largest group of bloggers, hundreds of them, concentrated on romantic poetry. So many blogging bards might be uncommon in many other countries, but in Iran it is simply a reflection of a culture that so reveres poetry, where many children grow up dreaming of becoming great poets in the way many young Americans dream of a future in sports.

The mapping program assigns each dot its place through factors including lists of words that it checks for and that indicate the likely focus of the blog: reformist, conservative or other.

For example, Masoud Dehnamaki is a conservative who helped found the Basiji, a hard-core group notorious for its bloody attacks against antigovernment demonstrators. In recent years he has become a documentary filmmaker, focusing on social problems like prostitution.

The large dot representing his blog sits almost at the middle of the map, indicating that it is popular among both conservatives and reformists. The dot representing the Web site of former President Mohammad Khatami, a moderate leader, sits to his left, deeper into the reformist field.

Mehrangiz Kar, an Iranian dissident in Boston who is aware of the project but not directly involved, said that over the long run the blogosphere would bring change within certain limits.

Bloggers are not permitted to criticize the Islamic system itself, Ms. Kar said, but they are far freer than writers for newspapers or other news media.

“These Web logs are very effective,” she said. “They create conversation. Not just about elections or democracy, but about cinema, theater, arts, literature. These fields are very important for changing that society.”