Parse data into three logs
To avoid repetitive code, make the Log class do only one of the three things it currently does, and create three instances instead:

class Log(object):
    def __init__(self, name):
        self.name = name
        self.data = {}

    def add_item(self, key, status, item_name, score):
        key = '%s %i' % (self.name, key)
        if key not in self.data:
            self.data[key] = {"Comp": defaultdict(int),
                         "Miss": defaultdict(int),
                         "Post": defaultdict(int),
                         "Add": defaultdict(int),
                         "Score": 0}

        self.data[key][status][item_name] += 1
        self.data[key]['Score'] = score

def update_views(log_file):
    daily_log = Log('Day')
    weekly_log = Log('Week')
    monthly_log = Log('Month')
    ...