What does this value mean?

[hoxesi8100@]

Subtract the observed value from the expected value.
Square the result to amplify the difference.
Divide this squared difference by the expected value.
Sum up all the results for each cell to get your total Chi-Square value.
Let’s work through the data from the earlier example:

Outcome

Subject Line A (O)

Subject Line B (O)

Subject Line A (E)

Subject Line B (E)

(O−E)2/E(O - E)^2 / E(O−E)2/E

Opened

550

450

500

500

(550−500)2/500=5(550-500)^2 / 500 = 5(550−500)2/500=5

Did Not Open

1,950

2,050

2,000

2,000

(1950−2000)2/2000=1.25(1950-2000)^2 / 2000 = 1.25(1950−2000)2/2000=1.25

Now sum up the (O−E)2/E(O - E)^2 / E(O−E)2/E values:

χ2=5+1.25=6.25\chi^2 = 5 + 1.25 = 6.25χ2=5+1.25=6.25

This is your total Chi-Square value, which czech republic phone number material indicates how much the observed results differ from what was expected.


You’ll now compare this Chi-Square value to a critical value from a Chi-Square distribution table based on your degrees of freedom (number of categories - 1) and confidence level. If your value exceeds the critical value, the difference is statistically significant.

7. Find your sum.
Finally, I sum the results from all cells in the table to get my Chi-Square value. This value represents the total difference between the observed and expected results.