Rail passengers bombarded train companies with nearly half a million negative tweets in the last 12 months.
Analysing key words in tweets such as "fault", "profit", "angry" and "frustrated", the CommuteLondon organisation found there had been 473,661 tweets from travellers using negative language in the 12 months ending in March.
The survey covered the 14 train companies operating services to London, and the company with the most negative tweets was Abellio Greater Anglia, with 72,861. WORDS: PA.
Next was First Great Western (FGW) with 64,302, followed by Southern with 61,715.
The company which generated the least number of negative tweets was Chiltern, with 5,676.
The 473,661 negative tweets also included many thousands related to the heating of carriages and crime on the railways, although not all these warmth/crime tweets were negative.
Based on key words such as "too hot" "air con" and sauna", Abellio Greater Anglia generated the most tweets - 1,677 - while FGW was second with 1,524 and South West Trains (SWT) third with 1,497.
Great Northern generated the fewest tweets, just 101, and in this "overwarm" category there were a total of 11,179.
On this basis, again Greater Anglia was the subject of the most tweets - 1,702. Next was FGW with 1,565, followed by Southeastern with 1,297. First Capital Connect had the least tweets, just 168, and all told, there were 12,076 in this category.
CommuteLondon also looked at how Twitter is used to report crime, with words such as "pick-pocket", "thieves" "fight" and "drunk" being looked for.
There were 7,408 tweets using crime language, with Greater Anglia having the most - 1,322. Next was SWT with 894, followed by Virgin Trains with 892.
Of total tweets, c2c and London Midland had the highest proportion related to crime.
CommuteLondon.com director Daren Wood said: "Commuters are increasingly using social media sites like Twitter to publicly express their frustrations about their daily journeys.
"Train operators should be actively monitoring these interactions to improve services and help create a happy commuter experience.
"The more commuters share opinions on daily train services, the more information operators will have make to the necessary improvements."
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