Analysis of the Yelp Dataset

Jerry Tsien
November 16, 2015

Introduction

Based on the Yelp dataset from http://www.yelp.com/dataset_challenge, this analysis tries to find the relationship between the rating of a business (how many stars it has) and the number of reviews it receives on the website of Yelp (http://www.yelp.com/).

  • The overall rating of a business is determined by majority voting (selecting the mode of all the individual ratings).
  • The number of reviews are counted regardless of their content.
  • For the purpose of this analysis, rating/stars and review count are calculated from the review file, rather than from the business file.

Methods and Data

  • The number of reviews for different ratings is plotted.
  • The percentage of businesses with higher ratings at different levels is calculated and plotted, in order to find the pattern.
  • When and where the pattern resembles a linear relationship, a regression model is established.

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Conclusions

  • More than 2/3 of all the businesses with reviews in the Yelp dataset are rated 4-star or 5-star.
  • The more reviews a business receives, the more likely it'll be rated 4-star or 5-star.
  • On average, 6 additional reviews for a business will increase the probability of its receiving 4 or 5 stars by 1%, when the number of reviews is less than 100.
  • When the number of reviews is above 50, more than 90% of these businesses are rated 4-star or 5-star.
  • It's impossible to separate 4-star businesses and 5-star ones solely by the number of reviews they receive.

Resources

Thank You!