Example: Ice Cream Sales												
												
The local ice cream shop keeps track of how much ice cream they sell versus the temperature of that day for the last 12 days:												
Formulate a null hypothesis and verify it by Pearsons and Spearman coefficients												
												
				Ho: there is no correlation between the number of ice cream sell and the temparature 								
				H1: there is a correlation between the number of ice cream sell and the temparature 								
												
				Spearman coefficients  								
	Temperature (°C)	Ice Cream Sales ($)			Rank temperature 	Rank ice cream sales 	difference 					
	14.2	215			11	11	0					
	16.4	325			9	10	-1					
	11.9	185			12	12	0					
	15.2	332			10	9	1					
	18.5	406			6	8	-2					
	22.1	522			4	3	1					
	19.4	412			5	6	-1					
	25.1	614			1	1	0					
	23.4	544			2	2	0					
	18.1	421			7	5	2					
	22.6	445			3	4	-1					
	17.2	408			8	7	1					
												
	N: 	12					14					
	N^3:	1728				rs:	0.951048951					
						critical value:	0.587					
												
					"Ho is rejected, there is a correlation between the number of ice cream sell and the temparature "							
												
				Pearsons coefficients  								
Average: 	18.7	402.42										
												
	Diferrences 											
	-4.5	-187.42	838.69		alpha: 	0.05						
	-2.3	-77.42	176.12		D.O.F	10						
	-6.8	-217.42	1473.00									
	-3.5	-70.42	244.70		r:	0.9575						
	-0.2	3.58	-0.63		critical value: 	0.576						
	3.4	119.58	409.57									
	0.7	9.58	6.95									
	6.4	211.58	1359.42		"Ho is rejected, there is a correlation between the number of ice cream sell and the temparature "							
	4.7	141.58	668.98									
	-0.6	18.58	-10.69									
	3.9	42.58	167.14									
	-1.5	5.58	-8.24									
												
	177.0	174754.92	5325.03