Campaign reach is one of the linchpins of successful content marketing. With the right media relations approach, your content marketing campaigns can tap into a publisher’s highly-engaged audience.

But, how do you know which publishers have the most engaged following? To approach this question strategically, we need to know which publishers are getting the most social media engagement, and how.

To find this out, we partnered with BuzzSumo to find the 1 million most-shared articles on social media from the top 190 publishers, and the number of shares they generated during the first half of 2014.

Once we established our dataset, we applied the Alchemy API to determine the sentiment of each piece, which yielded some interesting insights into the emotional tone of publishers and social networks.

Finally, we ran a corpus analysis to learn which words were most prevalent in the most-shared articles, and to see whether any patterns emerged.

Here, in two parts, we examine the social networks and publishers that are driving online sharing. (For the full report, you can download our white paper.)

Part I: Social Networks

Social media platforms vary widely in their number of users, the culture of their engagements, and how much their audience uses the network to actively share. To begin understanding how and why people decided to share these million articles, we started by learning more about where they were sharing.

1. Scale

We began by comparing the number of times articles were shared on each network. The 1 million articles in our study generated more than 2.6 billion shares combined on Facebook, Google+, LinkedIn, Pinterest and Twitter. However, the distribution of shares was not even, nor did it precisely correlate to the size of the social platform.

Facebook, inarguably the largest of the networks, did secure 81.9% of all the shares in this study – more than four times that of all the other networks combined. LinkedIn, the second largest network according to a recent study by Pew Research Institute, had the fewest shares with only 2.2%. But the smallest network, Twitter, saw nearly four times as many shares with 8.6% of the total share count.

The differences between the networks didn’t stop with their size and propensity to provoke sharing. In addition to the volume of content spread by each audience, we also found some compelling data on content types that are more popular on each network.

2. Sentiment

By employing the Alchemy API, we were able to analyze the sentiment of the most-shared articles on each network on a range of positive to negative. This provided us with this profile of the tones that resonate most on each social media channel:

Twitter and Google+ showed the most balanced range of sentiments in their 500 most-shared articles. In each case, slightly less than half of the articles were negative, slightly less than half were positive, and between 14% – 17% were ranked as neutral. Twitter trended slightly more negatively than Google+.

On LinkedIn and Pinterest, the stories shared by audiences ranged between 65% – 75% positive. Far and away the most positive of the group, their distributions of neutral and negative stories were relatively balanced at less than 20% in each category.

With 47% negative stories shared, the largest social network – Facebook – also turned out to have the most negative sentiment profile. This trend was even more striking when we removed articles from dominant publishers BuzzFeed, ViralNova, and Upworthy from the dataset; in that analysis, stories shared on Facebook appeared to be 57% negative. When we calculated sentiment both with and without those dominant publishers, positive stories remained between 30% – 36% and neutral stories ranged from 13% – 17%.

3. Language

Just as the networks’ audiences showed distinct preferences in the sentiment of the content they shared most, we also found that particular words showed up more frequently in the headlines shared most on different social media channels. To understand how language preferences vary by network, we analyzed the headlines of the top articles on each platform to parse out the most relevant and frequent keywords. We’ve compiled each network’s most prevalent headline keywords here:

What emerges from these word clouds is a picture of the topics that dominate content sharing on each network. Facebook audiences shared the most diverse mix of news, entertainment and commercial pieces, especially when BuzzFeed, ViralNova, and Upworthy articles were excluded.

On other networks, the most popular topics tended to represent a more narrow scope: Twitter’s most popular articles centered on pop culture; Google+ favored more world and industry news; Pinterest trended toward domestic, health, food, and beauty pieces; and LinkedIn shared professional development and business articles.

Part II: Publishers

Understanding the publishers whose content is being shared is as valuable as understanding the audiences sharing it. By examining their sentiments, headline wording and content-sharing metrics, we learn more about their social media strategies and how they are connecting with audiences.

1. Scales Of Success

In the vast world of internet publishing, it is difficult to say who is definitely winning at content sharing. Between the variables of share volume, different platforms, audience diversity and ROI, publishers are approaching audiences and seeing success in different ways.

In fact, this is one of our key takeaways from this study: No single publisher has become dominant in every category.

By Total Shares

With 408 million shares, BuzzFeed claimed more than 6% of the total 2.6 billion shares generated by the million articles in this study. This is 1.5 times more than second place publisher Huffington Post, which earned 268 million, and 3.4 times more than third place CNN’s 121 million.

While these numbers are staggering, they are not the norm; 94% of the publishers in this study earned less than 50 million shares, and 88% earned less than 25 million. (Even more striking – when we removed Facebook shares from the equation, 60% of publishers earned less than 1 million total shares.)

By Shares Per Article

How much content did publishers put out in order to garner all these shares? The answer varies by publisher. The top three content producers of the 1 million most-shared articles were Huffington Post (with 53,423 articles), New York Times (with 47,410 articles), and Daily Mail (with 45,950 articles). None of them received more than 5,000 average shares per article – in fact, Daily Mail earned less than 2,000.

Conversely, the two publishers that earned astronomically more shares per article than any other outlet – ViralNova and Upworthy – published very few articles comparatively. Upworthy published just 1,313 articles in this study, and ViralNova published even fewer at 703.

By Diversity Of Network Reach

When we looked at which networks were delivering the most shares for each publisher, we found that very few publishers had established a strong audience on all five platforms. In fact, six of the top 20 publishers in this study received 90% of their shares on Facebook alone. Only five outlets (above) ranked in the top five of most-shared publishers on more than one network – a signal to marketers that not all messages will succeed on all networks.

2. Sentiment

What made particular publishers successful with specific platforms? Strategy certainly plays a big part, but another piece of the puzzle is the makeup of the articles themselves. Because we found such distinct sentiment profiles among social networks, we also applied the Alchemy API to the top 500 articles from the top 20 publishers.

From our previous studies on viral emotions, we know that high-arousal emotions tend to trigger content sharing; this remained true when we saw that the most successful headlines routinely incorporated elements of surprise and curiosity.

We also found that while most publishers penned pieces that covered a range of sentiments, there were three exceptions: news outlets were predominantly negative, BuzzFeed and Upworthy were strikingly neutral, and Mashable was the most positive publisher of the group.

3. Words

The first thing we found when we applied a corpus analysis to all of the headlines in our study was that no specific topics dominated. The complete set of headlines did not reflect any trending subjects that created wins across the board; however, we did find that knowledge-based verbs such as know, understand, and prove were widespread, and positive adjectives like greatest and hilarious were used frequently.

When we looked more closely at the top headlines from specific publishers, we found a different story. The stories that were most shared on each social network were much more narrowly focused on the verticals and interests of each publication. We compiled word clouds of high performing headline keywords from six top publishers for you here:

Opinions expressed in this article are those of the guest author and not necessarily Marketing Land. Staff authors are listed here.