The sum of these 15 results is 68 and the average (mean) is therefore 68/15=4.53 approx. If the spin wheel is fairly balanced and it has 8 slots (0-7) the probability of falling on any slot is ⅛. The sample standard deviation of the mean is 2.39. This means you can expect the result to be between 4.53-2.39=2.14 and 4.53+2.39=6.92, so the wheel may be biased to fall between 2 and 7.
You could draw a histogram based on these results:
0 X
1 X
2 X
3 XX X
4
5 XX X
6 X
7 XXXXX
The histogram gives you the shape of the distribution. From this you can see that the wheel seems to fall on the high numbers more than on the low numbers. If the wheel were properly balanced you would have a uniform distribution and you would expect each number to appear about the same number of times. So for 15 spins you would expect each number to appear about twice. In this example 7 appears 5 times.