Twitter #Thatsafrican and #thingsdarkiessay hashtags after users complained that they found the hashtags offensive. There are allegations that Twitter removed #NaMOinHyd from the trending list and added an Indian National Congress-sponsored hashtag. There are numerous tools for adding content, monitoring content and conversations including Twitter's own TweetDeck, Salesforce.com, HootSuite, and Twitterfeed.com. , fewer than half of tweets posted were posted using the web user interface with most users using third-party applications (based on an analysis of 500 million tweets by Sysomos). In June 2009, after being criticized by Kanye West and sued by Tony La Russa over unauthorized accounts run by
Sampling (statistics) about 600 million tweets produced every day. It is not necessary to look at all of them to determine the topics that are discussed during the day, nor is it necessary to look at all the tweets to determine the sentiment on each of the topics. A theoretical formulation for sampling Twitter data has been developed. In manufacturing different types of sensory data such as acoustics, vibration, pressure, current, voltage and controller data are available at short time intervals. To predict down-time it may not be necessary to look at all the data but a sample may be sufficient. Survey