Spearman correlation - admission "During the admission procedure, the evaluation was performed by commissions and by a special program. " "Based on the ranking of the ten students, decide whether both assessments are dependent." Student A B C D E F G H I J commission grade 4 6 1 5 10 2 7 3 9 8 program grade 1 3 5 7 8 4 6 2 10 9 difference difference squared H0….correlation between the two grading =0 H1….correlation between the two grading <>0 ##### Sheet/List 2 ##### Test1 Test2 You are given test results (points) from two subjects of 8 randomly selected students. 80 65 Determine the correlation of a linear dependence of these results by the Spearman and Pearson coefficients. 50 60 36 35 58 39 72 48 60 44 56 48 68 61 ##### Sheet/List 3 ##### Data displays the association between the IQ of 10 adolescent in a sample with the number of hours they listen to rock music per month. Determine the strength of the correlation between IQ and rock music using both the Pearson’s correlation coefficient and Spearman’s rank correlation. Compare the results. IQ Rock m. rank IQ rank rock d 99 2 120 0 98 25 102 45 123 14 105 20 85 15 110 19 117 22 90 4 ##### Sheet/List 4 ##### 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 H0 there is no correlation between the number of ice cream sell and the temperature Spearman we accept H1 there is a correlation between the number of ice cream sell and the temperature Temperature (°C) Ice Cream Sales ($) Rank T° Rank ice cream differnce 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 14 N 12 rs 0.951048951 N^3 1728 Critical value 0.587 Pearsons averarge 18.7 402.4166667 dx*dy -4.5 -187.4166667 838.6895833 -2.3 -77.41666667 176.1229167 -6.8 -217.4166667 1472.997917 -3.5 -70.41666667 244.6979167 -0.2 3.583333333 -0.627083333 3.4 119.5833333 409.5729167 0.7 9.583333333 6.947916667 6.4 211.5833333 1359.422917 4.7 141.5833333 668.98125 -0.6 18.58333333 -10.68541667 3.9 42.58333333 167.1395833 -1.5 5.583333333 -8.235416667 -18.7 -402.4166667 7515.13125 525.7 336694.0903 12840.15625 r 0.965090023 d.f 0.576