Podcasts are available in a broad range of formats and content, and by a variety of producers. There are unique challenges with podcast recommendations that make it hard for users to distinguish between podcast episodes, and choose the right podcast to listen to. We see an opportunity to explain recommendations to users in order to help them make decisions about what to listen to. In this work, we study the characteristics of podcasts that make them diferent from each other. Based on a formative study with podcast experts, we find that host/guest information, format, length, and “vibe” are dimensions that constitute diferences among podcasts. In a user study, we tested how highlighting such dimensions with explanatory labels impact users in a podcast selection task.
podcast ecosystem, current podcast streaming platforms,
such as Apple Podcasts, Audible, Spotify and YouTube,
Podcasts, portable and on-demand spoken-word audio neither fully support listener exploration of the breadth
content available on a variety of streaming platforms, of available podcasts nor highlight the diferentiating
have emerged as a popular medium for information, en- dimensions among podcast shows and episodes. These
tertainment, and advertising [
Because of their low barrier to entry for both pro- unique and appealing content. For instance, podcasts
usuducers and listeners, podcasts encourage both amateur ally are released and organized in a series in the listening
producers and mainstream media to provide a variety of interface, where new podcasts are pushed to subscribers
content [
We found diversity of creators (e.g., ethnicity, genders,
age groups, social status, etc.), diferences of
presentation (interviews vs. storytelling), diferences in “vibe” [19]. In this subsection, we discuss what user interfaces
(light-hearted vs. more serious conversation), and difer- have been explored in the podcast ecosystem.
ences in length, to be particularly relevant. Our findings Current podcast interfaces are typically sequential and
suggest that listeners’ exploration of podcasts can be sup- organized by show-level [20], which could potentially
ported by showing content labels, and that these labels limit users’ ability to explore beyond the shows they
alcan increase users’ awareness of podcast diversity. ready listen to. Similar to other long-form and episodic
media (e.g., movies, television series, documentaries, etc.),
one challenge for podcasts is to summarize the most
inter2. Related Work esting content from the long and dense content [21]. Due
to the limitations of the audio format, which does not
sup2.1. Diferentiation in podcasts port skimming and browsing [22], it becomes a challenge
Finding a podcast among the large variety of available for listeners to navigate among podcasts. One possible
podcasts can be hard for users, since topical relevance is solution to ease the navigation of audio content is the use
merely one aspect. As previous research suggests [
One approach to help diferentiate between content is impacted by summaries.
via diverse recommendation so that users can navigate Apart from summaries, content labels are another
comand identify relevant items faster in the exploratory stage mon way to provide snippets of information about
con[15]. Several dimensions of diversity are highlighted by tent and enable users to filter content easily. In prior
previous studies [16], including diversity of entities (i.e., research, tags have been extensively studied as a form
people, group, and organizations), topic diversity, view- of content labels. Social tags can be used as a key
elpoint diversity (e.g., diferent angles), and medium diver- ement in recommendation systems [25]; diferent tag
sity (e.g., audio, video). Yet, these dimensions do not take selection algorithms as well as tag designs have been
podcasts’ unique attributes into account. For instance, tested and suggested in movie recommendations [26].
some non-textual attributes unique to podcasts may con- Previous studies have also investigated the reasons
betribute to a diferentiated listening experience, such as hind users’ tagging behaviors in photos [27]. The use of
energy, seriousness, vibe, novelty of the episode, dura- social tags can enhance navigation and search [28, 29].
tion, number of speakers, popularity, etc., as suggested Tags can also be combined with audio content for style
in previous research [
Though many studies have explored specific dimen- has been applied in web pages, movies, photos, and musions of how podcasts difer from each other, a holistic sic, but these studies do not fully understand how the view of how users perceive these diferences is underex- tags impact the user navigation process as well as users’ plored. As a result, we propose that providing ways to actual selections. diferentiate can help listeners make better choices. 2.2. Interface elements for podcast
diferentiation Users’ interactions with podcasts are influenced by the interfaces in which podcasts are presented [18], and many podcasters rely heavily on platforms to support discovery
We interviewed professional podcast curators and one designer to understand how they diferentiate between podcasts, and we sought to understand expert practices around supporting listeners’ exploration of various podcasts. Previous studies have shown the power of experts in understanding users’ needs [31, 32]. Therefore their This low barrier also allows bringing “individualistic” expertise and knowledge about the breadth of podcast perspectives into public discourse, or the intimate self content can ofer in-depth insights around users’ explo- [33], in contrast to the traditional standard. The intiration and navigation processes. macy from podcasters also makes podcast listening an
We recruited four interviewees, including three pod- intimate and personal listening experience for listeners. cast curators and one designer, through snowball sam- I2 discussed that podcasts are “just for myself” and “a pling at a podcast streaming company: I1 (male, three self-experience,” instead of for a group of people. Podcast years of experience in podcast curation), I2 (female, two listening is also a passive listening experience for most years of experience in podcast curation), I3 (male, two listeners and listeners listen to it for mainly entertainyears of experience in podcast curation) and I4 (male, less ment purposes. As I3 mentioned, listeners “use podcasts than one year of experience in podcast playlist design and to fill that space” when they “are commuting, cleaning, four years experience in audio design). All interviewees or some activity that’s mundane.” were also long-time podcast listeners. Each interview Another unique aspect about podcasts is that listeners was conducted virtually via video meetings and lasted have control over what they listen to. Listeners themfrom 46 to 72 minutes. selves choose what to listen to and decide “whether or
Our semi-structured interviews began with self- not this podcast is something that is worth listening to,
introduction questions to learn each interviewee’s profes- as opposed to the advertising world that tells you which
sional background and personal background in podcast are the podcasts that are most worth listening to.” (I1)
listening. We then asked interviewees to describe how I4 also discussed that discovering new podcasts is
pullthey diferentiate between podcasts, and their process focused, relying on users to make the decision, similar
of evaluating diverse and varied content for listeners, if to the active pull strategy discussed by [
Our interview results emphasize that podcasts ofer a variety of diferent voices to listeners. As I3 defined it, podcast diversity is “about hearing from people who are outside of your own normal circles” and “being exposed to diferent voices.” As mentioned before, the low bar4. Results rier to become a podcaster enables listeners to explore things from a diferent perspective, and the intimacy of podcasts also create a unique opportunity for listeners 4.1. Open format leads to varied content to personalize the listening experience from a diferent Our results highlight that podcasts are a unique medium angle. that ofers diversity naturally due to its low barrier to Our interviewees spoke about how podcasts difentry. As I1 mentioned, “barrier to entry creates a lot fer from each other, including diversity of creators of diversity...there’s no requirement to becoming a pod- (hosts/guests) from diferent backgrounds, ethnicity, gencaster.. as long as someone can hold a conversation on a ders, age groups, and social status (e.g. celebrities vs. nonsubject for an X amount of time, [and] there’s not even celebrities as mentioned by I1), diversity of opinions and a structure around it.” The low or no barrier to entry viewpoints, diversity of presentation (“how these things also creates such a unique opportunity for many voices are being discussed” as mentioned by I2), variations of to be “elevated” and surfaced, which is not common in “vibe” (e.g., light-hearted vs. more serious conversation other mainstream media formats. Meanwhile, as pod- as discussed by I1), diferences in popularity to “give casts become more and more popular, celebrities also use more opportunity to smaller podcasts” (I3), variations podcasts to voice their opinions. The mix of ordinary in formats and mixed media (e.g., conversational, storypeople and powerful voices in podcasts creates a diversity telling, music, etc.), diferences in topics (e.g., technology of voices in podcasts. Podcasts are “a great way to learn vs. meditation) (I4). Among all the dimensions, a wide about new topics or hear things from people you might variety of creators is most important, since it can also not have heard things from in your day-to-day life”(I3). naturally bring a diversity of viewpoints, as I2 argued. As suggested by our interview results, it is crucial to show a variety of “voices” when presenting podcasts to form that allows researchers to view and record particlisteners. In our study, we define a list of dimensions ipants’ experiences during their interactions with the that highlight the diferences between podcasts and then prototype. We recruited the participants from 20 to 35 we highlight those diferentiating dimensions in the pro- years old living in the United States, who subscribe to totype. This can be achieved by current shelf-like de- a podcast streaming service, listen to podcasts multiple signs or achieved by creating diferent tags/labels for times per week, and explore new podcast shows at least each episodes once per week. We excluded participants who failed to test all three interfaces, as well as participants who tested our prototype twice. In total, we recruited 34 participants. 5. Ongoing Work: Study With We collected qualitative feedback from participants about Explanatory Labels what they liked and disliked about the interface, as well as measures for perceived diversity of the recommendaAs a result of our formative study, we built a web applica- tions. tion that presents podcast recommendations to users in the interface shown in 1. Participants were instructed to use our web application to select one episode they would 6. Discussion like to listen to from 10 episodes shown on the interface.
The episodes were from the same topic to avoid any top- We investigate how users can better diferentiate among ical efects. Users could not proceed to the next interface the various kinds of podcast recommendations with launtil they listened to the chosen episode for at least five bels as a way to explain diferences to users. In a formaminutes. We followed a similar approach from [22] to tive study, we observed that diversity of creators (e.g., enable an organic exploration of podcasts. After partic- ethnicity, gender, age groups, social status, etc.), diferipants listened to the selected episode for five minutes, ences of presentation (interviews vs. storytelling), difthey were directed to a survey to reflect on their podcast ferences in “vibe” (light-hearted vs. more serious conexploration process, including naming the episode they versation), and diferences in length, to be particularly chose to listen to, providing a summary of the episode, relevant dimensions in helping people diferentiate beand the other questions mentioned in the next subsection. tween podcasts. Further, in a user study based on a web Once participants finished selections, they were asked to application that explains these dimensions through labels complete a questionnaire about their preferences on how and summaries, we observed that the label explanations well the interface helped the user perceive the diferences help users better diferentiate between varied podcast between the content, usefulness, and informativeness. episodes when summaries are provided, and listeners
The prototype interface (see Figure 1) has seven key selected more podcasts in total when explanations were components for each episode: Episode Image, Episode provided. These findings indicate that explanations for Title, Publisher, Episode Description, Host/Guest Infor- diferences in content may lead to more varied and dimation, Audio Preview, and Diversity Labels. We use the verse selection of content. term diversity to describe the diferentiating dimensions Our study suggests that listeners are able to better difof podcasts that we observed during the formative study. ferentiate between podcast episodes when the diferences
We chose a list of labels to explain the diferentiating of the content are highlighted via labels and summaries dimensions of each podcast. Based on host/guest infor- and chose more distinct and varied content. We also find mation, we had “Diverse Voices” to highlight podcasters that users were more satisfied with their podcast explofrom a wide variety of demographics. Based on the length ration experience when provided explanatory labels. This of each episode, we had “Deep Dive” for podcasts that are ifnding is consistent with prior research suggesting that very long (close to or more than 60 minutes) and “Quick users are more satisfied when they are made aware of Listen” for podcasts that are short (less than 10 minutes). the available options [34] and are presented with diverse Based on the vibe of each episode, we had “Serious Con- content [35, 36]. These findings are relevant for practiversations” and “Light-hearted Conversations”. Based tioners who design and build recommender systems for on format, we had “Solo Podcast”, “Interview Podcast” podcasts and other types of streaming content. If the and “Storytelling Podcast.” To amplify up-and-coming aim of these systems is to encourage diversity in conpodcasters, we had “New Voices” for podcasters who are sumption, providing recommendation explanations that new in podcast spaces. For our user study, we manually help scafold user awareness of the diversity of available labeled each episode with the applicable diversity labels content can potentially help achieve that goal. and highlighted these label(s) in blue to captivate users’ We propose that explaining and highlighting the diferattention to the diferent dimensions between podcast entiating dimensions between podcasts is a first step to episodes while exploring. understand how to recommend a diverse set of podcasts
We recruited participants on usertesting.com, a plat- to listeners. Diversity can help reflect existing diferences in societies, to give equal access to any diferent points of view and actors, and to ofer a wide range of choices for audiences[37]. From the individual perspective, listeners can be more satisfied with the options provided for them with an awareness of all the options and choices they have [34]. If listeners only encounter similar content, then they may find themselves in an echo chamber [ 38].
Furthermore, from the content creator perspective, it is essential for streaming platforms to encourage equitable opportunities for a diverse set of creators so listeners can encounter a broad spectrum of perspectives and backgrounds. A diverse exploration experience can then facilitate change of ideas and dialogues between diferent viewpoints and arguments so that users can have more informed opinions and become less polarized [39, 34].
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