Hi I have a dataset of the type attached. Here's my code thus far. dataset <-data.frame(read.delim("data", sep="\t", header=TRUE)); newData<-subset(dataset, select = c(Price, Reliability, Mileage, Weight, Disp, HP)); cor(newData, method="pearson"); Results are Price Reliability Mileage Weight Disp HP Price 1.0000000 NA -0.6537541 0.7017999 0.4856769 0.6536433 Reliability NA 1 NA NA NA NA Mileage -0.6537541 NA 1.0000000 -0.8478541 -0.6931928 -0.6667146 Weight 0.7017999 NA -0.8478541 1.0000000 0.8032804 0.7629322 Disp 0.4856769 NA -0.6931928 0.8032804 1.0000000 0.8181881 HP 0.6536433 NA -0.6667146 0.7629322 0.8181881 1.0000000
It appears that Wt and Price, Wt and Disp, Wt and HP, Disp and HP, HP and Price are strongly correlated. To find the statistical significance, I am trying sample.correln<-cor.test(newData$Disp, newData$HP, method="kendall", exact=NULL) Kendall's rank correlation tau data: newx$Disp and newx$HP z = 7.2192, p-value = 5.229e-13 alternative hypothesis: true tau is not equal to 0 sample estimates: tau 0.6563871 If I try the same with sample.correln<-cor.test(newData$Disp, newData$HP, method="pearson", exact=NULL) I get Warning message: In cor.test.default(newx$Disp, newx$HP, method = "spearman", exact = NULL) : Cannot compute exact p-value with ties > sample.correln Spearman's rank correlation rho data: newx$Disp and newx$HP S = 5716.8, p-value < 2.2e-16 alternative hypothesis: true rho is not equal to 0 sample estimates: rho 0.8411566 I am not sure how to interpret these values. Basically, I am trying to figure out which combination of factors influences efficiency. Thanks Lalitha
Price Country Reliability Mileage Type Weight Disp. HP 8895 USA 4 33 Small 2560 97 113 7402 USA 2 33 Small 2345 114 90 6319 Korea 4 37 Small 1845 81 63 6635 Japan/USA 5 32 Small 2260 91 92 6599 Japan 5 32 Small 2440 113 103 8672 Mexico 4 26 Small 2285 97 82 7399 Japan/USA 5 33 Small 2275 97 90 7254 Korea 1 28 Small 2350 98 74 9599 Japan 5 25 Small 2295 109 90 5866 Japan NA 34 Small 1900 73 73 8748 Japan/USA 5 29 Small 2390 97 102 6488 Japan 5 35 Small 2075 89 78 9995 Germany 3 26 Small 2330 109 100 11545 USA 1 20 Sporty 3320 305 170 9745 USA 1 27 Sporty 2885 153 100 12164 USA 1 19 Sporty 3310 302 225 11470 USA 3 30 Sporty 2695 133 110 9410 Japan 5 33 Sporty 2170 97 108 13945 Japan 5 27 Sporty 2710 125 140 13249 Japan 3 24 Sporty 2775 146 140 10855 USA NA 26 Sporty 2840 107 92 13071 Japan NA 28 Sporty 2485 109 97 18900 Germany NA 27 Compact 2670 121 108 10565 USA 2 23 Compact 2640 151 110 10320 USA 1 26 Compact 2655 133 95 10945 USA 4 25 Compact 3065 181 141 9483 USA 2 24 Compact 2750 141 98 12145 Japan/USA 5 26 Compact 2920 132 125 12459 Japan/USA 4 24 Compact 2780 133 110 10989 Japan 5 25 Compact 2745 122 102 17879 Japan 4 21 Compact 3110 181 142 11650 Japan 5 21 Compact 2920 146 138 9995 USA 2 23 Compact 2645 151 110 15930 France NA 24 Compact 2575 116 120 11499 Japan/USA 5 23 Compact 2935 135 130 11588 Japan/USA 5 27 Compact 2920 122 115 18450 Sweden 3 23 Compact 2985 141 114 24760 Japan 5 20 Medium 3265 163 160 13150 USA 3 21 Medium 2880 151 110 12495 USA 2 22 Medium 2975 153 150 16342 USA 3 22 Medium 3450 202 147 15350 USA 2 22 Medium 3145 180 150 13195 USA 3 22 Medium 3190 182 140 14980 USA 1 23 Medium 3610 232 140 9999 Korea NA 23 Medium 2885 143 110 23300 Japan 5 21 Medium 3480 180 158 17899 Japan 5 22 Medium 3200 180 160 13150 USA 2 21 Medium 2765 151 110 14495 USA NA 21 Medium 3220 189 135 21498 Japan 3 23 Medium 3480 180 190 16145 USA 3 23 Large 3325 231 165 14525 USA 1 18 Large 3855 305 170 17257 USA 3 20 Large 3850 302 150 13995 USA NA 18 Van 3195 151 110 15395 USA 3 18 Van 3735 202 150 12267 USA 3 18 Van 3665 182 145 14944 Japan 5 19 Van 3735 181 150 14929 Japan NA 20 Van 3415 143 107 13949 Japan NA 20 Van 3185 146 138 14799 Japan NA 19 Van 3690 146 106
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