You might think Amazon is the cheapest place to go for online purchases, but a new study has revealed this isn't always the case. Researchers have found that the Seattle-based company fools users into thinking they are getting a good deal by tweaking their prices a number of times each hour. Overall, the study found that the online marketplace harnesses the 'psychology of price perception' in buyers by making millions of individual price changes a day. Scroll down for video. Researchers have found that the Seattle-based company fools users into thinking they are getting a good deal by tweaking their prices, such as on the pictured router, a number of times each hour. For instance, when it's offering its biggest discounts on popular products, such as a TV, it will increase the prices of its less popular items to make a profit. According to a white paper by Boomerang Commerce, the technique means Amazon often appears to be beating its competition on low prices. 'Amazon may not actually be the lowest-priced seller of a particular product in any given season,' the report reads. 'But its consistently low prices on the highest viewed and best-selling items drive a perception among consumers that Amazon has the best prices overall – even better than Walmart.' One example is when a best-selling router (pictured) was priced 20 per cent below Walmart's price, a different model was priced at 29 per cent more expensive than it cost on Walmart. Last month, a glitch allowed online shoppers to buy their products on Amazon for 1p. Some firms lost tens of thousands of pounds in a single hour during Friday night’s disastrous software malfunction. Customers cashed in by placing 1p orders in bulk, in a ‘supermarket sweep’ on products ranging from clothes and toys to home furnishings and health products. Some took to Twitter to boast of ordering goods worth thousands of pounds for a few pence. The problem affected firms on Amazon’s Marketplace – which allows independent sellers to offer their goods alongside Amazon’s own – using third-party business software called RepricerExpress. It is designed to keep them competitive by automatically repricing items on Amazon so they are cheaper than others in the digital market. News of the pricing glitch spread fast on social media, with dozens of people taking to Twitter to report the bargains they had snapped up thanks to the technical glitch. Amazon said many orders had been cancelled. Boomerang uses the example of a $350 (£230) Samsung TV that was discounted $250 (£165) on Black Friday. But at the same time, Amazon increased the price of the HDMI cable needed for the TV, as the product would not change the price perception of the larger purchase. Another example, according to Business Insider, is when a best-selling router was priced 20 per cent below Walmart's price, a different model was priced at 29 per cent more expensive than it cost on Walmart. 'Competitive pricing has moved beyond weekly adjustments and price matching,' said Guru Hariharan, founder Boomerang Commerce. 'The Producer Price Index sheds light on the complexity and the speed at which retailers adjust their pricing to drive buyers and revenue.' Overall, the study found that the online marketplace harnessing the 'psychology of price perception' in buyers by making millions of individual prices changes a day.

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Online marketplace makes millions of individual price changes a day. For instance, when a best-selling router was priced 20 per cent below Walmart's price, a different model was priced 29 per cent more expensive. Study found when Amazon offers big discounts on popular products, such as a TV, it will increase the prices of its less popular items to make a profit. This technique harnesses the 'psychology of price perception' in buyers.

Manchester United captain Wayne Rooney 'cheated' to win a penalty at Preston, insists Stan Collymore. The forward went over after being challenged by North End goalkeeper Thorsten Stuckmann, before picking himself up to convert the resulting spot-kick that put United 3-1 up on Monday. But debate surrounded about whether Rooney had dived to win a penalty, with former England striker Gary Lineker tweeting: 'A dive? Yes. A reckless challenge? Yes. An interesting one.' Wayne Rooney touched the ball past North End goalkeeper Thorsten Stuckman during the FA Cup clash. Rooney went down a moment after and several of the Preston players were unhappy with his actions. Rooney lies down on the ground before the penalty is given by the referee late on at Deepdale. But Collymore was in no doubt that Rooney was guilty of diving: 'Rooney shouldn't be diving due to his position as captain of club and country,' said on talkSport. 'He toe-pokes the ball past the goalkeeper, who he knows is coming out quickly, and he dives,' said Collymore. 'That’s cheating, we’ve had this debate a million times.' He added: 'When you wear that respect campaign armband, you owe it to the fans and the game not to do that. 'I’m bitterly disappointed, he is the England captain and Manchester United captain and he’s better than that.' Rooney scored from the spot-kick to put Manchester United 3-1 up on the night. Collymore's view that Rooney was echoed by former Preston player Kevin Kilbane, who said: 'There's no contact on Wayne Rooney. It's a dive.' However, Preston manager Simon Grayson refused to criticise Rooney, despite believing Stuckmann had not touched the United captain. ‘Wayne Rooney has not been touched by the goalkeeper. Yes he has had to jump out of the way but he has not been touched. I’m not saying it wasn’t a penalty, I’m saying there was no contact. You can interpret that how you want,' said Grayson. ‘It wasn’t a dive. He has gone to get out of the way and take evasive action. I’ m not complaining.' Former footballer Stan Collymore believes Rooney shouldn't be diving because of his position in the game. Rooney was defended by former United team-mate Phil Neville and England manager Roy Hodgson. Neville said: 'Wayne Rooney had to get out the way. For me it's a reckless challenge.' Hodgson said: 'I don't think it is a dive, he's taking evasive action.'

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Wayne Rooney 'cheated' against Preston, believes Stan Collymore. The 29-year-old scored a penalty as Manchester United beat Preston 3-1. Collymore believes Rooney owes it to the fans and game not to dive.