Dataset: the dataset can be downloaded on http://jmcauley.ucsd.edu/data/amazon/
Function of different file
Sentimen analysis:
input: the original jsondataset
output：a new json dataset where reviewText is replaced by its normalized sentiment score
write:
input: the json dataset with sentment score
output: a new json dataset where helpful is replaced by its normalized weight
cred:
calculate the reliability of each user
reliability:
calculate the weight of each tip of review