The most known lottery in Poland: you cross 6 out of 49 numbers. 6 are drawn from pool.
The chance for hitting all 6 is 1:13 983 816
You can win 2,5mln EUR
Bitcoin, chance of hitting a block a day with 70 Gigahash (I mine for fun with) is 1:14 993 148
You can win about 180k EUR
Actually buying a lottery ticket every day to win 2,5mln EUR is wiser.
A great analysis but I have reasons to believe that it's a bit far from accurate, the 1 in 13m chance you have with the lotto is once every week, while the odds for hitting a block which you mentioned is based on a shot every day, so for this to be a bit more accurate you need to multiply the lotto ticket cost by 7, and then if we were to assume that the average lifespan for the miner is 2 years, then you will need to multiply that by 730, so if the ticket price is 2$, you will pay $1,460 to match the number of trials that a miner can have.
I am aware that there are other prize catogires of 3,4,5 matches but I think the prize is too small ot be considered, you also need to keep in mind that when you hit a bitcoin block you keep all the rewards and nobody can share them with you, where in the lotto, you are subject to share the prize with x amunt of people, on the othre hand, playing the lotto means you won't have to pay the power bill, no matiance, no cleaning no dead PSUs or a firmware glitch.
There are many more factors invovled to determine which would be econcmically better, I don't have the time, skills nor the desire to do that in-depth analysis (pehabs someone who does play the lotto and solo mine at the same time can do it) but I do tend to agree that perbaps and most likely playing the lotto is cheaper than solo mining.
With that being said, Solo mining is way more fun!!

Probability ...
1 in xxx chance for lotto is EVERY GAME played, not every week.
1 in xxx chance for BTC is EVERY BLOCK mined, not every day.
Mathematically, the probability is the same no matter which way you approach it. However, with BTC, the chances are (like Lotto) that the more hashrate you have (the more Games in Lotto), the larger the chance of winning simply due to the amount of different plays. It is still the same probability with each hash/games played, but the chances (ie - risk of loss) are different.
This is why any form of gambling (especially trading - which is a complex form of gambling) have their risk. The difference is, that with Lotto, a games may NOT win, whereas with BTC (or almost any other Crypto) a block WILL be hit at certain interval.
So a Lotto win is NEVER guaranteed regardless of it's probability, whereas a block to be hit is an ABSOLUTE CERTAINTY every 10minutes or thereabouts. It is just a matter of whether YOU hit the block. Lotto has no inbuilt certainty - EVER.
#crysx
I do not agree on the "Absolute Certainty" Part. It is just an on-average-solution-timespan derived from the Poisson Distribution Probability. There were periods when the time between two blocks found were 3 hours for example.
If you want to calculate the true probability you need to consider every hash value and its chance of beeing below the current difficulty level. Lets go for the 70GH/s. Say the current Diff is 20T and for BTC the Diff Value when 1 corresponds to 8 leading hex numbers which means 2 to the power of 32 in binary. So roughly 4,3 billion hashs in decimal system necessary to find such a value on average. Multiplay this with 20.000 billion (20T) and you get the chance for each single hash calculated of beeing below that threshold. For such small possibilities you can simply sum them up, the deviation is negletable. But please consider this isnt possible anymore for "probable" events. If you would control the complete BTC Hashrate your Chance of finding a Block in 10 mins is around 63% and not 100% when you sum all hashs up (your machines would have calculated the above mentioned amount of hashs in that time) but as stated at the beginning the probabilty is a distribution. To achieve 100% your integral would need to be 1 and that means to integrate to infinity. Which is hard to achieve if we believe our state of the art science that the universe is finite in regard of its lifespan