at first down load this file here for nothing,
zoom out the sheet.
(1) what is chi- square test and Pearson and Yates
(2) chi-square distribution
(3) Odds ratio, Risk Ratio, Risk Difference and their 95% confidence interval
(4) Phi and Cramer's V
(5) some charts fit to chi- square test. you can copy and paste Word or PowerPoint and modify them easily.
(6) only fill new number Yellow Cells!!!! Do not change other cells
And Now we follow the old man's thought
we make the final number.
the number is "chi-square"
Who made this number? Pearson made it.
The son of Pear? Not actually he is the father of Statistics.
The larger this number, the bigger the difference between expected and observed.
This is Pearson's thought and it is reasonable.
Now he made a nice conclusion.
the possibility that two table is same = p
p=0.005~ so two table is not same.
One scholar named Yates made a small change the number X2
So we call this new number 'Yates X2'
'Yates X2' is more accurate when the cell is small.
if the cell is large, Two X2 get closer.
yes we say the possibility be p=0.005
but "How much different"
there are many ways
(1) odds ratio
(2) risk ratio(=relative risk)
(3) risk difference
(4) Cramer V and phi
you can choose one in your paper and power point.
(1) odds ratio
usually for cross-sectional study
odds itself ratio between two observation.
(2) risk ratio(=relative risk)
usually for cohort study
risk usually include observation after time(period)
(3) risk difference
usually for cohort study
risk usually include observation after time(period)
relatively no so popular but increasing
especially for non-inferiority test
all three are written with it 95% confidence interval
(4) Cramer V and phi
two values are same (when 2X2 table)
not so common
similar to correlation coefficient
Three chart are easy to understand.
you can copy and paste in your paper(MS word) and slide(powerpoint)
and modify them
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