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May 29 2013

16:51

What’s New in Digital Scholarship: Teen sharing on Facebook, how Al Jazeera uses metrics, and the tie between better cellphone coverage and violence

library-shelves-of-academic-journals-cc

Editor’s note: There’s a lot of interesting academic research going on in digital media — but who has time to sift through all those journals and papers?

Our friends at Journalist’s Resource, that’s who. JR is a project of the Shorenstein Center on the Press, Politics and Public Policy at the Harvard Kennedy School, and they spend their time examining the new academic literature in media, social science, and other fields, summarizing the high points and giving you a point of entry. Roughly once a month, JR managing editor John Wihbey will sum up for us what’s new and fresh.

This month’s edition of What’s New In Digital Scholarship is an abbreviated installment — we’re just posting our curated list of interesting new papers and their abstracts. We’ll provide a fuller analysis at the half-year mark, in our June edition. Until then, happy geeking out!

“Mapping the global Twitter heartbeat: The geography of Twitter.” Study from the University of Illinois Graduate School of Library and Information Science, University of Illinois at Urbana-Champaign, published in First Monday. By Kalev Leetaru, Shaowen Wang, Guofeng Cao, Anand Padmanabhan, and Eric Shook.

Summary: “In just under seven years, Twitter has grown to count nearly three percent of the entire global population among its active users who have sent more than 170 billion 140-character messages. Today the service plays such a significant role in American culture that the Library of Congress has assembled a permanent archive of the site back to its first tweet, updated daily. With its open API, Twitter has become one of the most popular data sources for social research, yet the majority of the literature has focused on it as a text or network graph source, with only limited efforts to date focusing exclusively on the geography of Twitter, assessing the various sources of geographic information on the service and their accuracy. More than three percent of all tweets are found to have native location information available, while a naive geocoder based on a simple major cities gazetteer and relying on the user — provided Location and Profile fields is able to geolocate more than a third of all tweets with high accuracy when measured against the GPS-based baseline. Geographic proximity is found to play a minimal role both in who users communicate with and what they communicate about, providing evidence that social media is shifting the communicative landscape.

“Predicting Dissemination of News Content in Social Media: A Focus on Reception, Friending, and Partisanship.” Study from Ohio State, published in Journalism & Mass Communication Quarterly. By Brian E. Weeks and R. Lance Holbert.

Summary: “Social media are an emerging news source, but questions remain regarding how citizens engage news content in this environment. This study focuses on social media news reception and friending a journalist/news organization as predictors of social media news dissemination. Secondary analysis of 2010 Pew data (N = 1,264) reveals reception and friending to be positive predictors of dissemination, and a reception-by-friending interaction is also evident. Partisanship moderates these relationships such that reception is a stronger predictor of dissemination among partisans, while the friending-dissemination link is evident for nonpartisans only. These results provide novel insights into citizens’ social media news experiences.”

“Al Jazeera English Online: Understanding Web metrics and news production when a quantified audience is not a commodified audience.” Study from George Washington University, published in Digital Journalism. By Nikki Usher.

Summary: “Al Jazeera English is the Arab world’s largest purveyor of English language news to an international audience. This article provides an in-depth examination of how its website employs Web metrics for tracking and understanding audience behavior. The Al Jazeera Network remains sheltered from the general economic concerns around the news industry, providing a unique setting in which to understand how these tools influence newsroom production and knowledge creation. Through interviews and observations, findings reveal that the news organization’s institutional culture plays a tremendous role in shaping how journalists use and understand metrics. The findings are interpreted through an analysis of news norms studies of the social construction of technology.”

“Teens, Social Media and Privacy.” Report from the Pew Internet & American Life Project and Harvard’s Berkman Center for Internet & Society. By Mary Madden, Amanda Lenhart, Sandra Cortesi, Urs Gasser, Maeve Duggan, and Aaron Smith.

Summary: “Teens are sharing more information about themselves on social media sites than they have in the past, but they are also taking a variety of technical and non-technical steps to manage the privacy of that information. Despite taking these privacy-protective actions, teen social media users do not express a high level of concern about third-parties (such as businesses or advertisers) accessing their data; just 9% say they are ‘very’ concerned. Key findings include: Teens are sharing more information about themselves on their social media profiles than they did when we last surveyed in 2006: 91% post a photo of themselves, up from 79% in 2006; 71% post their school name, up from 49%; 71% post the city or town where they live, up from 61%; 53% post their email address, up from 29%; 20% post their cell phone number, up from 2%. 60% of teen Facebook users set their Facebook profiles to private (friends only), and most report high levels of confidence in their ability to manage their settings: 56% of teen Facebook users say it’s ‘not difficult at all’ to manage the privacy controls on their Facebook profile; 33% Facebook-using teens say it’s ‘not too difficult’; 8% of teen Facebook users say that managing their privacy controls is ‘somewhat difficult,’ while less than 1% describe the process as ‘very difficult.’”

“Historicizing New Media: A Content Analysis of Twitter.” Study from Cornell, Stoneybrook University, and AT&T Labs Research, published in the Journal of Communication. By Lee Humphreys, Phillipa Gill, Balachander Krishnamurthy, and Elizabeth Newbury.

Summary: “This paper seeks to historicize Twitter within a longer historical framework of diaries to better understand Twitter and broader communication practices and patterns. Based on a review of historical literature regarding 18th and 19th century diaries, we created a content analysis coding scheme to analyze a random sample of publicly available Twitter messages according to themes in the diaries. Findings suggest commentary and accounting styles are the most popular narrative styles on Twitter. Despite important differences between the historical diaries and Twitter, this analysis reveals long-standing social needs to account, reflect, communicate, and share with others using media of the times.” (See also.)

“Page flipping vs. clicking: The impact of naturally mapped interaction technique on user learning and attitudes.” Study from Penn State and Ohio State, published in Computers in Human Behavior. By Jeeyun Oh, Harold R. Robinson, and Ji Young Lee.

Summary: “Newer interaction techniques enable users to explore interfaces in a more natural and intuitive way. However, we do not yet have a scientific understanding of their contribution to user experience and theoretical mechanisms underlying the impact. This study examines how a naturally mapped interface, page-flipping interface, can influence user learning and attitudes. An online experiment with two conditions (page flipping vs. clicking) tests the impact of this naturally mapped interaction technique on user learning and attitudes. The result shows that the page-flipping feature creates more positive evaluations of the website in terms of usability and engagement, as well as greater behavioral intention towards the website by evoking greater perception of natural mapping and greater feeling of presence. In terms of learning outcomes, however, participants who flip through the online magazine show less recall and recognition memory, unless they perceive page flipping as more natural and intuitive to interact with. Participants perceive the same content as more credible when they flip through the content, but only if they appreciate the coolness of the medium. Theoretical and practical implications will be discussed.”

“Influence of Social Media Use on Discussion Network Heterogeneity and Civic Engagement: The Moderating Role of Personality Traits.” Study from the University of Alabama, Tuscaloosa, and the University of Texas at Austin, published in the Journal of Communication. By Yonghwan Kim, Shih-Hsien Hsu, and Homero Gil de Zuniga.

Summary: “Using original national survey data, we examine how social media use affects individuals’ discussion network heterogeneity and their level of civic engagement. We also investigate the moderating role of personality traits (i.e., extraversion and openness to experiences) in this association. Results support the notion that use of social media contributes to heterogeneity of discussion networks and activities in civic life. More importantly, personality traits such as extraversion and openness to experiences were found to moderate the influence of social media on discussion network heterogeneity and civic participation, indicating that the contributing role of social media in increasing network heterogeneity and civic engagement is greater for introverted and less open individuals.”

“Virtual research assistants: Replacing human interviewers by automated avatars in virtual worlds.” Study from Sammy Ofer School of Communications, Interdisciplinary Center Herzliya (Israel), published in Computers in Human Behavior. By Béatrice S. Hasler, Peleg Tuchman, and Doron Friedman.

Summary: “We conducted an experiment to evaluate the use of embodied survey bots (i.e., software-controlled avatars) as a novel method for automated data collection in 3D virtual worlds. A bot and a human-controlled avatar carried out a survey interview within the virtual world, Second Life, asking participants about their religion. In addition to interviewer agency (bot vs. human), we tested participants’ virtual age, that is, the time passed since the person behind the avatar joined Second Life, as a predictor for response rate and quality. The human interviewer achieved a higher response rate than the bot. Participants with younger avatars were more willing to disclose information about their real life than those with older avatars. Surprisingly, the human interviewer received more negative responses than the bot. Affective reactions of older avatars were also more negative than those of younger avatars. The findings provide support for the utility of bots as virtual research assistants but raise ethical questions that need to be considered carefully.”

“Technology and Collective Action: The Effect of Cell Phone Coverage on Political Violence in Africa.” Study from Duke and German Institute of Global and Area Studies (GIGA), published in the American Political Science Review. By Jan H. Pierskalla and Florian M. Hollenbach.

Summary: “The spread of cell phone technology across Africa has transforming effects on the economic and political sphere of the continent. In this paper, we investigate the impact of cell phone technology on violent collective action. We contend that the availability of cell phones as a communication technology allows political groups to overcome collective action problems more easily and improve in-group cooperation, and coordination. Utilizing novel, spatially disaggregated data on cell phone coverage and the location of organized violent events in Africa, we are able to show that the availability of cell phone coverage significantly and substantially increases the probability of violent conflict. Our findings hold across numerous different model specifications and robustness checks, including cross-sectional models, instrumental variable techniques, and panel data methods.”

Photo by Anna Creech used under a Creative Commons license.

May 03 2012

13:53

How We Got Here: The Road to Public Lab's Map Project

Last week, Public Laboratory announced that public domain maps are now starting to show up on Google Earth and Google Maps. But how did the projects get there? Here's a timeline of a Public Laboratory map project.

Making a map

Public Laboratory projects take a community-based approach to making maps that differs depending on where you are and the reason you want to create a map. People map areas for a number of reasons, including because there's a need to monitor an area of environmental concern, a dynamic event is happening that there's a desire to capture, or you cannot find adequate aerial image data. Before going out to map, preparing for fieldwork starts with the Public Lab map tools page, where you can discover what type of equipment to use and how to safely use it. Multiple research notes on how to do things such as setting up a dual camera rig and stabilizing the camera with a picavet can help with specific problems, but there are also hundreds of people in the online Public Lab community of mapmakers, sharing tips and experiences on the site.

Upon return

After the mapping flight, the map making begins with backing up the images and sorting through the set, making a subset for map production. Depending on the time in the air, there will be hundreds and sometimes thousands of individual images. Depending on the area of interest, you can hone in on which images will be used in creating the map. Assuming the flight was at a steady altitude, the images that you want to select are the sharpest ones that are vertically oriented. If you have many images for the same area, pick the best one, but also pick overlapping images so that there is plenty of overlap among the different images in the next step.

mapmill.jpg Public Laboratory's MapMill.

Images can be sorted locally or online. Public Laboratory created an online tool where a group can do collaborative selection. MapMill.org is a web-based image sorting and ranking tool where multiple users can sort through a large dataset simultaneously.

Map production

With a smaller set of the best images on hand, the images can be dynamically placed on the map in a process known as georectification. After all the images have been added to the map, the project is exported. The MapKnitter export tool does all of the geographic information systems crunching behind the scenes with the geospatial data abstraction library (gdal.org) and produces a GeoTIFF map file. The GeoTIFF format is a public domain metadata standard that embeds geographic information into the image TIFF file. At this point, the map is now in an interchangeable format that can be easily distributed.

MapKnitter.jpg Public Laboratory MapKnitter web-based aerial image map production tool.

Public Laboratory Map Archive

Public Lab hosts its own map data archive for storing and sharing finished map projects. Each map in the archive has a "map details page" that hosts details such as: title, date, place, location, resolution, field map maker, field notes, cartographer, ground images, oblique images from the flight, and comments from website users. The map participants choose whether to publish the map as Public Domain, Creative Commons Attribution ShareAlike, Creative Commons Attribution, or Creative Commons Attribution Non-Commercial.

occupy-oakland.jpg Public Laboratory Occupy Oakland, November 2, 2011 -- General Strike map in Google Earth.

Maps are viewable on the archive itself, and you can subscribe to it as an RSS feed. However, it's also a place for distribution of the data. As we announced last week, Google Earth has started licensing our public domain maps. Google Earth plans to continue to publish public domain maps from the Public Lab Archive a few times a year.

It's quite exciting to see these Public Labs maps go online with a ubiquitous data provider such as Google. We look forward to more people participating in this activity, and more publishing of public domain data.

rifle.jpg Google published some of the maps to Google Maps as well as Google Earth, which makes those maps widely accessible in the web browser and on mobile applications that use Google Maps.

January 04 2012

15:20

Public Lab Produces Wetlands Maps From Balloon and Kite Flights

The Public Laboratory for Open Technology and Science (PLOTS) is an organization and membership community which develops and applies open-source tools to environmental exploration and investigation. Public Laboratory's mapping tools, openly available and easy to use, are putting the ability to do processes such as georectifying in the hands of people who may have never created a map. 

Using aerial mapping techniques, residents and volunteers of the Gulf Coast region began field mapping trips in 2010 to document the impact of the BP oil spill. Between May 2010 and April 2011, tens of thousands of images were collected and 50 regional maps created. Between May and October 2011, Public Laboratory partnered with Dr. Alex Kolker, from the Louisiana Universities Marine Consortium to begin a bi-monthly monitoring of select oil impacted and non-impacted sites in the Barataria Bay region. The intent of this phase of wetlands mapping was to monitor change over time with high-resolution aerial and ground imagery.

slong-image00.jpg
Wilkinson Bay in Louisiana.

MAKING MAPS WITH GEORECTIFICATION
The fieldwork that goes into collecting images is the first step in creating maps. On the back end, the next step involves georectification -- the process where balloon and kite aerial images are "published" into geographic data. Simply, it is the alignment of an aerial image with a map or other spatial data of the same area. This part of the process is where images become maps and are associated with geographic standardized formats so that other users and programs can exchange and experience them in the same context.

Public Laboratory map production has used some specific techniques in creating wetlands maps. The maps are made through a georectification process by which adjacent images from the flights are merged in overlay as they are aligned to existing mapping information. Different "base" data can be used in these types of projects. In this case, we're georectifying the imagery through examination of the new images with existing imagery.

slong-image02.jpg

A new unaligned image (right) about to be georectified with the other imagery. The base layer is visible in the background.

Distortion correction is applied to the new images, and they're moved around so that the same features of the base map are in perfect overlay with the new image on top. In the bayou setting where lots of change is occurring on the outer coastlines, features such as vegetation composition and interior waterways are used to match each overlay. Although waterways in marshland may shift quite rapidly, the center of a 3-way intersection is quite stable, as a rule.

Matching the imagery based on the interior features has proven effective in this simple map-making technique. While the outer coastline in our new images has changed since the time of the base data, the process of fitting the imagery with all of the interior ground control features allows us to discover where the coastline is with some measure of confidence. Or to put it differently -- when the alignment happens with the historic data in most of the image, then the new areas can be extrapolated with regularity.

slong-image01.jpg

The image is aligned in overlay with the base data during the georectify process.

Visit the Public Lab site for guides and discussion about the process and to view image sets and maps that have already been published in the map archive. The archive is a home and distribution channel for published open-source maps.

Visit MapKnitter.org to learn about our map-stitching tools and to view maps that are being created by people who are using aerial mapping techniques in new ways to document and monitor sites and events that are of importance to their community.

April 20 2010

08:52
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