To put it simply, a METASCORE is a weighted average of reviews from top critics and publications for a given movie, TV show, video game, or album.
The basic concept is the same for each of the genres currently included in our site. Let's use a fictional movie -- 'Iron Chef vs. Godzilla' -- as an example.
Our staffers will go through every publication on our Movies Publications list (see below) looking for reviews for Iron Chef vs. Godzilla. For each review found, we will take the score given by the critic and convert it to a 0-100 point scale (For those critics who do not provide a score, we'll assign a score from 0-100 based on the general impression given by the review). These individual critic scores are then averaged together to come up with an overall score.
This overall score, or METASCORE, is a weighted average of the individual critic scores. Why a weighted average? When selecting our source publications, we noticed that some critics consistently write better (more detailed, more insightful, more articulate) reviews than others. In addition, some critics and/or publications typically have more prestige and respect in their industry than others. To reflect these factors, we have assigned weights to each publication (and, in the case of movies and television, to individual critics as well), thus making some publications count more in the METASCORE calculations than others.
In addition, for our movie and music sections, all of the weighted averages are normalized before generating the METASCORE. To put it another way that should be familiar to anyone who has taken an exam in high school or college, all of our movies and albums are graded on a curve. Thus the METASCORE may be higher or lower than the true weighted average of the individual reviews, thanks to this normalization calculation. Normalization causes the scores to be spread out over a wider range, instead of being clumped together. Generally, higher scores are pushed higher, and lower scores are pushed lower. Unlike in high school, this is a good thing, since it provides more of a distinction between scores and allows you to better compare scores across movies (or albums).
The resulting METASCORE, then, is a good indication of how a particular movie/game/album/television show was reviewed. The better the reviews, the higher the score will be; the worse the reviews, the lower the score will be. Ideally, if reviews are completely divided between good and bad, the METASCORE should be close to 50.