###Hi guys!

Despite it’s Bank Holiday today in the UK, there’re no bad times to studying. So, I woke up in this morning and started searching for new information and activities on the web.

Then, I realised I had subscribed myself to this Hacker Rank statistical competition one week ago, and it’d start this Monday. I ran to the website www.hackerrank.com and after a couple of news reading, the challenge began.

The first puzzle was kind of difficult to me. When I figured out I could use some functions, as sum(), mean() and others (Because I was trying to solve by creating functions, e.g., Sum = Len(x)/n), it explained 80% of the puzzle. However, for Mode() function, it didn’t work. Trying to write a code and looking for help in Google search, I found some help: someone wrote code to calculate the statistical mode in few lines. Then, I changed it a little bit and joined in my code lines, submitted and it worked! I will post the answer here next Monday or it’d be against the competition’s rules. They’ll release three puzzles per day, resulting in 21 puzzles in total! OMG!

This competition made me realise I need to study Statistics and Maths urgently.

So, I’ll post some basic concepts here to further consideration:

Mean: it is just the average of the n values observed.

Sample Standard Deviation: The sample standard deviation, s, is often a more useful measure of the spread than the sample variance, S-square, because S has the same units (inches, pounds, etc.) as the sampled values and mean of x.

One very useful concept is ANOVA table, which means Analysis of Variance: it tests the hypothesis that the means of two or more populations are equal. ANOVAs assess the importance of one or more factors by comparing the response variable means at the different factor levels.

This picture above show an ANOVA table built in Excel 2013, what is very simple to do. I’ll teach you later to do this. However, the critical skill is interpreting this small table within numbers.

See what each column means in Statistics:

SS = Sum of Squares df = Degrees of Freedom MS = Mean Squares F = F Test P-value = P-value

My explanation wasn’t for dummies in Statistics; later I’ll explain better about all of these concepts.

See ya!

Sources: http://support.minitab.com/minitab/17/topic-library/modeling-statistics/anova/basics/what-is-anova/ .DOC found in Google.co.uk http://graphpad.com/support/faq/the-anova-table-ss-and-df-in-two-way-anova/