Question

A quality control chart has been maintained for the weights of paint cans taken from a conveyor belt at a fixed point in a production line. Sixteen (16) weights obtained today, in order of time, are as follows:

64.7 32 1693150 ,MI 653 642 GYS, 68S, 66 66?70.1 70.4 66.8 65.0 68.9 63.6 66.8 69.3 71.6

Use the run test, at approximately a 0.01 level, to determine whether the weights of the paint cans on the conveyor belt deviate from randomness. Show your steps. If using a program, use R.

Answer 1

output :

> library(randtests)

> x=c(68.2,71.6,69.3,71.6,70.4,65.0,63.6,64.7,65.3,64.2,67.6,68.6,66.8,68.9,66.8,70.1)

> runs.test(x,pvalue = 0.99)

Runs Test

data: x

statistic = -1.0351, runs = 7, n1 = 8, n2 = 8, n = 16, p-value < 2.2e-16

alternative hypothesis: nonrandomness .

note: here, p-value is very less, and in this case , we reject the null hypothesis.