Chi-Squared Dance

Lyrics © 2015 Dominic Dousa and Lawrence M. Lesser, Music by Dominic Dousa

In a two-way table, blood types are the rows
And birth months are the columns – that's just how we chose.
The chi-squared test can tell us the answer to this question:
Do the categories interact? Is there a connection?

Compare expected counts to values we observed:
We will answer YES if a large gap occurred.


So birth months is in columns and blood types that's in rows.
The two are independent under our H-O.
Now we have 12 columns and also have 4 rows
That we have 33 degrees of freedom that we must know.

The chi-squared distribution has a long right tail:
That's the tail we focus on to see if H-O fails!