The number of contaminant particles (?aws) found on each standard size silicon wafer produced at a certain manufacturing site is a random variable, X. In order to characterize this random variable, a random sample of 30 silicon wafers selected by a quality control engineer and examined for ?aws resulted in the data shown in the table below, a record of the number of ?aws found on each wafer.
|
4
|
1
|
2
|
3
|
2
|
1
|
2
|
4
|
0
|
1
|
|
3
|
0
|
0
|
2
|
3
|
0
|
3
|
2
|
1
|
2
|
|
3
|
4
|
1
|
1
|
2
|
2
|
5
|
3
|
1
|
1
|
Postulate an appropriate theoretical probability model for this random variable and estimate the unknown model parameter(s). Include an estimate of the precision of the estimated parameters. State any assumptions you may need to make in an- swering this question.