#!/usr/bin/env Rscript
# author: John Lekberg
# date: 2016-02-10
#
# This is for part 9 of assignment 2.
# It deals with analysis of my data set.
#
# Copyright (c) 2016 John Lekberg
#
# Permission is hereby granted, free of charge, to any person obtaining a copy of
# this software and associated documentation files (the "Software"), to deal in
# the Software without restriction, including without limitation the rights to
# use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
# of the Software, and to permit persons to whom the Software is furnished to do
# so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in all
# copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.
gg <- read.csv("GameGrumpsData.csv")

# Coerces `publishedAt` to a string, so dates can be compared.
# The dates used are in ISO 8601 format, so they can safely be
# compared lexicographically.
gg$publishedAt <- as.character(gg$publishedAt)

# Produce the dummy variable to determine who was hosting the show
gg$era <- as.factor(ifelse(gg$publishedAt < "2013-06-20", "Jon", "Dan"))

# Get rid of all data newer than three months before 2016-01-24.
# This is because very new videos are less likely to have as many views,
# comments, likes and dislikes.
gg <- gg[gg$publishedAt < "2015-10-24", ]

# Only keep "Game Grumps" videos, not spin off series like "Steam Train"
# or "GrumpCade", etc.
gg <- gg[grepl("Game Grumps", gg$title),]

##################################
# Comparing Jon-Era and Dan-Era. #
##################################

t.test(gg$likeCount ~ gg$era)
t.test(gg$dislikeCount ~ gg$era)
t.test(gg$commentCount ~ gg$era)
t.test(gg$viewCount ~ gg$era)