Question

Populations may be _____________ or ________________________. A real population is one in which all observations are ______________________________ at the time of sampling. A hypothetical population is one in which all observations are _____________________________ at the time of ___________________. Often it is not convenient or even possible to include all observations in a research project. In such cases, a _____________________ or subset of observations is taken. The size of the sample is partially determined by estimated ___________________________among observations and by an acceptable amount of _______________________. In order to use inferential statistics, the analysis must be based on a ____________________ sample. A sample is random, if at each stage of the sampling, the selection process guarantees that all remaining __________________ have ____________________ chances of being selected. The observations in a randomly selected sample should be ___________________ of those in the population. However, there is no guarantee of this. The term random describes the process, and not necessarily the outcome. One of the best-known techniques for selecting a random sample is the ________________ method. All observations must be represented on slips of paper that are deposited in a bowl and _________________. The through stirring is a very important aspect of this method of sample selection. Another method for generating a random sample involves the use of the table of ____________ numbers. When using this table, the number of digits actually used is determined by the ____________ __________________. This method is not very efficient for obtaining a sample from a ____________ population. In an experiment, although subjects may not be selected randomly, they should be randomly assigned to either the experimental or control condition. The purpose of random assignment is to make sure that, except for __________________ differences, groups of subjects are similar with respect to any ____________________________________________. It is usually desirable that _____________ numbers of subjects be assigned to the experimental and control groups. To accomplish this, assignment should be done in ______________________.

Answer 1

Populations may be real or hypothetical. A real population is one in which all observations are available in solid form at the time of sampling. A hypothetical population is one in which all observations are not available in solid form at the time of sampling. Often it is not convenient or even possible to include all observations in a research project. In such cases, a set or subset of observations is taken. The size of the sample is partially determined by estimated among observations and by an acceptable amount of precision. In order to use inferential statistics, the analysis must be based on a random sample. A sample is random, if at each stage of the sampling, the selection process guarantees that all remaining observations have same chances of being selected. The observations in a randomly selected sample should be values of those in the population. However, there is no guarantee of this. The term random describes the process, and not necessarily the outcome. One of the best-known techniques for selecting a random sample is the lottery method. All observations must be represented on slips of paper that are deposited in a bowl and mixed(stirred) thoroughly. The through stirring is a very important aspect of this method of sample selection. Another method for generating a random sample involves the use of the table of random numbers. When using this table, the number of digits actually used is determined by the digits listed in the table. This method is not very efficient for obtaining a sample from a large population. In an experiment, although subjects may not be selected randomly, they should be randomly assigned to either the experimental or control condition. The purpose of random assignment is to make sure that, except for characteristics differences, groups of subjects are similar with respect to any experimental and control groups.. It is usually desirable that equal numbers of subjects be assigned to the experimental and control groups. To accomplish this, assignment should be done in equal-sized groups.