STAT 214 Exam (UL) with Correct Answers Rated A+

Statistics - The study of procedures for collecting, describing, and drawing conclusions from information. A science that falls under math because of the number of formulas. Population. Sample - What are the two sources of information? Population - Entire collection of individuals about which information is sought. Doesn't have to be a large group. Census - Collection of information from everyone in the population Parameter - Numerical measurement that describes a characteristic of a population. Result of census (means, proportions, standard deviations). Sample - Subset of the population containing the individuals actually observed. Do this if we cannot get information from everyone in the population. Sample Data - Collection of information from a sample Statistic - Numerical measurements that describe characteristics of a sample. Result of sample data. Represent. Sampling. - Ideally, we want the sample we choose to _____ the population appropriately. Since this is rarely possible, we use methods of ____ (choosing a sample) that give a better chance of the sample reflecting the major characteristics of the population under consideration Simple Random Sample. Samples of Convenience. Stratified Sampling. Cluster Sampling. Systematic Sampling. Voluntary Response Sample - What are the 6 methods of sampling? Simple Random Sample - A simple random sample of size n is a sample chosen by a method in which each collection of n population items is equally likely to make up the sample. Most common type. Choosing a group of n subjects that every group has a chance to be chosen. Example is there are 19,216 students at UL last fall and you might chose groups of n=50 Samples of Convenience - A sample that is not drawn by a well-defined method/ Not done often because of bias. May be okay if the sample does reflect the population appropriately. Not representative of the entire population. Stratified Sampling - A sample in which the population is divided into groups, called strata, where the members of each stratum have similar characteristics. Then a random sample is drawn from each stratum. Each strata may differ from one another although members of each strata tend to be alike. Example is freshman, sophomores, juniors, and seniors are all different between groups but within groups there are similar characteristics