Question

Osbornc, Bishop, and Klcin collectod manufacturing data on the torques required to loosen bolts holding an assembly on a picce of heavy machincry. The accompanying table shows part of their data concerning two particular bolts. The torques recorded (in ft lb were taken trom 15 different pleces ot equipment as they were assembled. al Make a scatterplot of these paired data. Are there any obvlous patterns in the plot? b) A trick otten employed in the analysis of the paired data such as these is to reduce the pairs to ditterences by subtracting the values of one of the varlables from the other. Compute ditferences top bolt-bottom bolt) here. Then make and interpret adot dlagram or these values Piece Top Bolt Bottom Bolt 110 115 115 125 115 115 115 120 120 110 115 125 110 10 130 110 75 120 12 110 115 13 110 120 115 15 105 105

Answer 1

Answer:

a) Use Minitab to get the required Scatterplot as shown below Scatterplot of Bottom Bolt vs Top Bolt 125 120 E 115 110 105- 110 90 100 120 130 Top Bolt From the above plot it is clear that there is no specific relation between the two variables

b) Compute the differences for the given data. Top Bolt Bottom Bolt Difference 125 -15 110 115 115 -20 125 105 115 120 0 115 -5 115 120 120 -5 115 110 125 125 110 105 20 110 130 -25 120 95 -5 115 110 -10 120 110 -20 115 95 105 105

Dotplot of Difference 18 6 12 -12 -6 -24 -18 Difference From the above plot it is clear that there are some outliers in the difference data and most of the differences are 0s. The difference data have approximately normal distribution.