Music popularity index

A music popularity index is a recorded music ranking, classified by popularity, which can be measured in many different ways. Nowadays, they are very common in musical websites, since they offer really interesting statistics which can be used for different applications, like musical recommendations. There are hundreds of ways to measure how popular an artist is and usually each website has its own measurement system. Although, the leading systems are the ones which follow:

Last.fm is Internet's reference to musical social networks. It has a huge database, based on all the information provided by their users when they listen to music in different ways, storing all the information in their profiles.

Every week, Last.fm updates its music charts, based on all the information stored last week by the millions of users through the Audioscrobbler plug-in or the Last.fm radio. The website has many different charts, including Top Artists, Top Tracks, Top Albums, Weekly Top Artists and Weekly Top Tracks. The Top Tracks and the Top Albums of an artist are also available. In a user's profile we have his/her Top Tracks and Top Artists. All these information can be classified in different time periods, such as last week, last month, last 3 months, last 6 months, last year or overall.

Since the generated music charts depend on what the users register and on the tags from their music files, Last.fm made up a system based on the listens of the users which corrects a song's tag if it differs from what most people registered. On the other hand, the system has errors, like not noticing the difference between two artists with the same name or not taking track length into consideration. Artists with many short tracks will have many more listens than artists with a few but very long ones.

The website ReverbNation also has joined the great amount of uprising musical social networks, contributing with their particular version. They developed a system to measure artists' popularity called Band Equity.

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Wikipedia