Definition of Criteria for Impact Analysis

A work in progress

Christoph Fuchs

Overview

1. What I won't talk about

2. Twofold

3. Classical social network analysis

4. Criteria in the online world

5. Specific definition of criteria

6. Open questions

What kind of impact?

I will not talk about impact in the "real world"!

Such as...

• Total revenue

• Offline bookings

• Offline sales

• ...

What I will talk about

Impact of actors and shared items on online social platforms.

Looking for impact criteria which are

• accessible(via automatic retrieval)

• independent of platform specifics

Two kindsImpact analysis is twofold

Two kinds of impact analysis

• actor level (potential impact)"Who is the most important guy?"

Two kinds of impact analysis

• item level (impact after publication)"What is 'hot' right now?"

In other terms

= page post

• Impressions"...measure the number of times a post from your Page is displayed, whether the post is clicked on or not."

• Reach"...measures the number of people who received impressions of a Page post."

"Classical" vs. "Online"

• Classical social network analysiso actor centric

• Online impact analysiso item centric

Classical Social Network Analysis

aka Graph Theory

Measures from "classical"Social Network Analysis

All* classical approaches are on the actor level.

• Centrality

• Prestige

• described by Wasserman and Faustin 'Social Network Analysis'

* at least all I have found so far.

Who is the "most important guy"?

Centrality

Centrality measure

C(actor) = [0 .. 1]

Normalized on the graph size.

Online: Where does your graph end?

Centrality

• Degree Centrality"Who has the most ties to other actors?"

• Closeness Centrality"How close is an actor to all the others?"

• Betweenness Centrality"Interactions between two nonadjacent actors might depend on the other actors in the set of actors, especially the actors who lie on the paths between the two."

Degree Centrality

"Who has the most ties to other actors?"

Cdinbound(orange) = 4 [normalized: 4 / 5 = 0.8]

Cdoutbound(orange) = 3 [normalized: 3 / 5 = 0.6]

Cdoutbound(green_women)

= 0.2

Closeness Centrality"How close is an actor to all the others?"

Online problem: Where does your graph end?Relevant for the online world?

Betweenness Centrality"Are you between any important actors?"

Online problems- Mostly direct communication (to immediates)- Distance can be easily reduced to 1

Prestige

• Degree PrestigeIndegree of each actor.

• Proximity PrestigeBased on average distance of actors in an influence domain.

• Status or Rank Prestige"If one’s influence domain

is full of prestigious actors, one’s prestige should also be high. If, however, an actor’s domain contains only peripheral, or marginally important, actors, then the rank of this actor should be low."

Criteriain the online world

Criteria?

• Connections between actors

• May be directed connectionso Indegree of connectionso Outdegree of connections

Criteria?

• Connections translated in terms of social platformso Facebook: x is a friend of yo Twitter: x is following yo YouTube: x subscribed to yo ...

Criteria?

• There may be different types of connections

• A platform may supporto Some kind of friendship relationo Some kind of subscriptionso ...

Platform specific criteria

• Some platforms have a form of reputation measurements

Item level

• "How many people have seen it?"

• "How many people have clicked on it?"

Item level

• "How many people have reacted on it? And how did they react?"o Like (+1, thumbs up, ...)o Favouriteo Reply or comment

• "How many people have re-shared it?"

Criteria?

• All kinds of criteria...o Views and clickso Unary feedbacko Binary feedbacko Ratingso Re-publication

Criteria?

• ... and moreo Replies (may not be text)o Commentso Sentiment of comments

Criteria?

• Platform specific exampleso MoodsDeviantARTo Bumpingvarious Forumso Pull Requests, Forks, Watches

githubo ...

What to make of it?So many things to measure!

We need

impact criteria which are

• accessible

• independent of platform specifics

Actor level criteria

• Connections between actorsMay be directed connections

o in- and outdegree of connections

Actor level criteria

Criterion (#) Value

Actors who are friends with you Integer

Actors whom you are friends with Integer

Actors who want to be friends with you [*] Integer

Actors you want to be friends with [*] Integer

Actors subscribed to your stream ("following" you) Integer

Actors to whom you are subscribed Integer

Reputation score [?] Integer

[*] Are those important?[?] Not sure about available reputation scores - platform dependency.

Item level criteria

Criterion (#) Value

Views Integer

Clicks Integer

Positive unary feedback Integer

Special unary feedback Integer

Negative unary feedback Integer

Re-publications Integer

Replies Integer

Comments Integer / Text

Sentiment Hash with Integer

Open Questions...or "Problems"

• What about re-publications?o broadens the 'impact area'o you don't have access to data outside your

immediate peerso It may be important who re-published it.

Almost impossible to measure how many times an item has been viewed if it goes viral.

Open questions

Is normalization important?

• Normalizationo Usually dependent on graph sizeo Online social network graphs are huge!

Open questions

Is the actor's reputation important?

• What about...o the success of previously published items?o the sentiment of previously published items?o Is any publicity good publicity?

Open questions

• Weighingo What criteria are the most important?

Re-publication >? Like

• Combination across platformso One platform may only have 'Like'o Online social network graphs are huge!

Open questions

• Algorithm?o Can existing classical approaches be used?o Existing open-source algorithms?o Is performance important?

To be investigated...

Open questions

Thank you.Questions?

Discussion!