I'd like to create a ranking system for my site. Similar to something like HotorNot.com . Is this very hard to do/ what programming do I need to know and If it was difficult what do you think the cost would be for someone to make a system like for me would be? Thanks!
What programming you need to know? I suppose you know none. If you are just getting started it will be a litle dificult to get things up and running in a short ammount of time. Your better options are to search google for ratings scripts and compare prices.
If you have a database it's fairly simple. For instance with products... You create a table just for ratings with a field for the product id, the rating (1-10, 1-100, whatever you want). then you let people rate it with a simple form that records the data... id|productid|rating 1|310|5 2|310|7 3|400|9 To show the average rating you would query the ratings table for all entries where product id is found... lets say "310" ... You get 2 results. You add the ratings together and divide the number of results and you have your ave. rating of 6. Depending on how much more complicated you want it, you could probably find someone on rentacoder.com to do it very cheap.
what algorithms could be there? standart system, nothing hard you need to think about architecture, not algorithms. So, first you need to think what do you want to get in results. Again, much work could be done for administrator's control panel - all depends on your need. If you want to start serious project- I could help
if you want to use css rating try http://komodomedia.com/blog/index.php/2006/01/09/css-star-rating-part-deux/ link and demo http://www.cssremix.com for css rating