A survey is conducted to determine the most common reason people own a cell phone. A company sent out a survey to customers between the ages of 20 and 30. Based on the responses the company concluded that people own a cell phone for messaging purposes. Is this conclusion valid? No because not all people who own a cell phone have the same probability of being selected? Yes because the sample includes all customers between the ages of 20 and 30? Yes because the sample includes male and female customers? Or no because the simple includes customers of too many different ages?
The conclusion is not valid because not all people who own a cell phone have the same probability of being selected. The survey only targeted customers between the ages of 20 and 30, which may not be representative of all cell phone owners.
