Theory of Control Charts (continued) DCOVA Control charts indicate when changes in data are due to: Special or assignable causes Fluctuations not inherent to a process -Represents problems to be corrected Data outside control limits or trend Chance or common causes -Inherent random variations Consist of numerous small causes of random variability Statistics for Managers Using Microsoft ExcelStatistics for Managers Using Microsoft Excel Theory of Control Charts  Control charts indicate when changes in data are due to:  Special or assignable causes  Fluctuations not inherent to a process  Represents problems to be corrected  Data outside control limits or trend  Chance or common causes  Inherent random variations  Consist of numerous small causes of random variability (continued) DCOVA