Quality Associates Case Study
Random samples of 30 will allow for swift action If said processes are not producing at efficient levels or drop below an average of 12 units, the null hypothesis, which has been set for this particular operation. Corrective action shall be taken anytime the experimental hypothesis tested does not equal 12.
Taking 30 samples at continuous hourly Intervals four times during the day and hypothesis testing them resulted In corrective action being taken one out of three times. The first sample had a test statistic of -1. 7 which led to sample 1 being . 303 above the given acceptable levels. The second hypothesis test statistic equaled . 713 with a .
1 69 above the first sample’s level of significance and was also not rejected. The third sample resulted in a test statistic reading of -2. 935 with a level of significance . 004 below the acceptance level of . 01 and corrective action was taken. The last sample delivered a test statistic of 2.
161 and a . 039 significance level with no corrective action because it was . 029 above the level of rejection.
Further testing of the data with the four samples produced standard deviations of . 22036, . 22036, .
2071 7, and . 206611, respectively. All four samples are reasonably within the set assumption of . 21 which can safely be assumed as to be a reasonable point estimator for this sampling operation because the variation is not outrageously outside of the mean set. With a population mean of 12 the process would be deemed as operating satisfactorily because the upper limit of the tail equals 12.
27 and the lower limit equals 1 1. 7.
The sample average falls between these limits and corrective action should not be taken for quality control purposes. Increasing the level of significance would result in more immediate corrective actions taken but also more unnecessary corrective actions. The null hypothesis will be rejected and production halted more times even when operation levels are satisfactory. Type 1 error rates will positively correlate with the increased number of errors.
The sample mean of 800 observations using samples of 30 at hourly rotations has been found satisfactory.
Hypothesis testing proved that the operation was operating satisfactorily three out of four samples. The standard deviation of . 21 was found reasonable. Computing the Limits for the sample mean of 12 also proved the operation was performing satisfactorily.
More samples are needed for further testing to decrease the variation levels. BY -runner if said processes are not producing at efficient levels or drop below an average of 12 Taking 30 samples at continuous hourly intervals four times during the day and hypothesis testing them resulted in corrective action being taken one out of three times.
The first sample had a test statistic of-I . 027 which led to sample 1 being . 303 with a . 169 above the first sample’s level of significance and was also not rejected.
20717, and . 206611, respectively. All four samples are reasonably within the set should not be taken for quality control purposes. Increasing the level of significance samples. The standard deviation of . 21 was found reasonable.
Computing the limits
