What values to choose for correlation?

Question

To work out correlation I'm using the online calculator : http://easycalculation.com/statistics/correlation.php

Data set 'A' : 
value1 = 1;
value2 = 1;
value3 = 1;
value4 = 1;

Data set 'B' : 
value1 = 1;
value2 = 1;
value3 = 1;
value4 = 1;

For these values the correlation between 'A' & 'B' is 'invalid'

For correlation I need to assign each value a unique number ? How do I decide these values and how they should increase, or does it matter what these values are as long as they are unique ?

Something like :

Data set 'A' : 
value1 = 1;
value2 = 2;
value3 = 3;
value4 = 4;

Data set 'B' : 
value1 = 1;
value2 = 2;
value3 = 3;
value4 = 4;

or :

Data set 'A' : 
value1 = 1;
value2 = 1.1;
value3 = 1.2;
value4 = 1.3;

Data set 'B' : 
value1 = 1;
value2 = 1.1;
value3 = 1.2;
value4 = 1.3;

The reason I can choose the values is that I am basing it group of users and words associated with them. For example here is a dataset that contains usernames and they words associated with those users :

username, associated words
user1   , test1,test2,test3
user2   . test3,test4

Can I associate any value with these words as long each value is distinct and is the same for each user ? Each word has a distinct value, test3 has value 3, so the above dataset becomes :

username, associated word values
user1   , 1,2,3
user2   . 3,4

But I can also change these values, so test3 now has a value of 6 and should not affect correlation since I have changed the value from 3 to 6 for bother user1 & user2 ? :

username, associated word values
user1   , 1,2,6
user2   . 6,4

Answer 1

The Pearson correlation is used to measure the strength of linear relationship between two continuous variables $X$ and $Y$, and hence it does not fit the purpose here.