In: Statistics and Probability
A computer factory is planning to change their production process. They hire 18 new employees and half of them applies the new production process while the other half applies the old procedure. The length of time in minutes required for each employee to assemble the computer is recorded at the end of the month. The resulting measurements are shown in the following table. We know that the samples are independent. Assume normally distributed assembly times and assume that the variances of the assembly times are equal for the two methods. Estimate the true mean difference (Old-New) with 90% confidence interval and decide which assembly method is better.
Procedure Measurements
Old 32 37 35 28 41 44 35 31 34
New 35 31 29 25 34 40 27 32 31