
Superball one (data x) 
Superball two (data y) 
b1 
63 
47 
b2 
65 
77 
b3 
66 
76 
b4 
68 
74 
b5 
69 
75 
b6 
69 
71 
b7 
70 
68 
b8 
70 
72 
b9 
71 
83 
b10 
71 
80 



n 
10 
10 
mean 
68.2 
72.3 
st dev 
2.7 
9.89 
mean diff 
4.1 

c 
0.95 

α 
0.05 

tc 
2.26 

se 
3.24 

E 
7.33 




1 
3.23 < µ <11.43 
ci includes zero, includes no difference as possibility. Not significant 
2 
Yes 

3 
No 

4 
0.23 
pvalue > 0.05: not significant. 
5 
No 

6 
Fail to reject 

7 
No 


Maximum confidence of difference 


0.77 





Difference in the means not significant 
Difference in the means significant 

[Either pairwise or for independent samples] 
Confidence interval approach 
Zero is in the confidence interval for the difference of the means 
Zero is not in the confidence interval for the mean difference 
alpha α 
Our willingness to risk rejecting a true null hypothesis 
Pvalue approach 
pvalue is greater than alpha 
pvalue is less than alpha 
Max c 
max c is less than 1α 
max c is greater than 1α 
result 
fail to reject the null hypothesis 
reject the null hypothesis 
Difference is real? 
No 
yes 
Change is real? 
No 
yes 
statistically significant? 
No 
yes 
If type I risk is 0.05 
pvalue > 0.05 
pvalue < 0.05 