Download
1 / 8
80 likes | 91 Views
California Standards. SDAP2.2 Identify different ways of selecting a sample (e.g., convenience sampling, responses to a survey, random sampling) and which method makes a sample more representative for a population. Vocabulary. systematic sample convenience sample
E N D
California Standards SDAP2.2 Identify different ways of selecting a sample (e.g., convenience sampling, responses to a survey, random sampling) and which method makes a sample more representative for a population.
Vocabulary systematic sample convenience sample self-selected sample
Recall that in a random sample each member of the population has an equal chance of being selected. Some other types of sampling methods are described below.
Additional Example 1: Identifying Sampling Methods The manager of a company wants to know how many employees have a laptop computer at home. Identify each type of sampling method. A. The manager randomly chooses 40 names from a list of all employees. This is a random sample because every employee has an equal chance of being selected. B. The manager surveys the first 50 employees as they arrive at the office. This is a convenience sample because the group of employees is easy to reach. C. The manager places a stack of survey forms in the company cafeteria. This is a self-selected sample because the group of employees chooses whether to complete the surveys.
Check It Out! Example 1 You want to know how often students in high school take tests. Identify each type of sampling method. A. You survey the first 50 students as they arrive at school. This is a convenience sample because the group of students is easy to reach. B. You place a stack of survey forms in the student library. This is a self-selected sample because the group of students chooses whether to complete the surveys. C. You randomly choose 40 names from a list of all students and then every 5th name after that. This is a systematic sample because the students are chosen at random and then the other names are chosen by using a pattern.
Random samples and systematic samples are more likely to be representative of a population than either convenience samples or self-selected samples.
Additional Example 2: Analyzing Sampling Methods Determine which sampling method will better represent the entire population. Justify your answer. Jon’s sample is a random sample, giving every band member an equal chance to be surveyed, so it is the better method.
Check It Out! Example 2 Determine which sampling method will better represent the entire population. Justify your answer. Ferdinand’s method produces results that better represent the entire swimming team population.
