Belly Button Ratios
__________ Height in inches.
__________ Long Measure - The distance from your belly button to the bottom of your foot in inches.
__________ Short Measure - The distance from the top of your head to your belly button in inches.
__________ First Ratio = height/long measure
__________ Second Ratio = long measure/short measure
Put your ratios on the board separated by gender.
Homework: run hypothesis tests to determine if there is a gender difference.
Note in the small sample size n study below, the differences are not significant.
	Gender	First	Second		Gender	First	Second
Sylvia	F	1.66	1.58	Ertin	M	1.6	1.66
Meranda	F	1.69	1.46	Lee Ling	M	1.68	1.47
Anastasia	F	1.67	1.49	Serafin	M	1.65	1.23
Agnes	F	1.61	1.8	Kevin	M	1.63	1.58
Kesarina	F	1.67	1.5	A-1	M	1.73	1.37
Carolyn	F	1.67	1.44
Kiumy	F	1.63	1.53
	n	7	7			5	5
	mean	1.6540	1.5431			1.6572	1.4624
	stdev	0.03	0.12			0.05	0.17
	mean difference	-0.0032	0.0807
	Ho: µ1-µ2=0
	Ho: µ1-µ2<>0
Hyp	pooled 1/√n	0.5855	0.5855
Test	degrees freedom	10	10
	pooled s	0.0382	0.1436
	t-statistic t	-0.1432	0.9605
	t critical tc	2.2281	2.2281
	p-value	0.8890	0.3595
	max c	0.1110	0.6405
Conf	Error E	0.0498	0.1873
Int	mean diff – E	-0.0530	-0.1066
	mean diff	-0.0032	0.0807
	mean diff + E	0.0466	0.2681
	Both include zero: Zero cannot be
	ruled out as a possible pop value
Section 9.4: If n were equal, solve for n. Note that using tc will overestimate n, which is
considered a "conservative" approach. Better to overestimate than underestimate.
The desired Error E would be equal to or less than the mean difference.
	n	1412.27	31.39
In theory the first and second ratios approach the Fibonacci Ratio:
	=(1+SQRT(5))/2
	1.6180