*Inferential statistics refers to the methods used by scientists to go from results of research studies to conclusions about theories or applied procedures. *The normal curve (normal distribution) is a bell-shaped, unimodal, symmetrical distribution. In addition, approximately 34% of the scores in a normal curve are located between the mean and 1 standard deviation from the mean, and an additional 14% of the scores are located between 1 standard deviation from the mean and 2 standard deviations from the mean. *Probability ("p") is the expected relative frequency of a particular outcome and is usually figured as the proportion of a certain possible outcome-i.e., the number of a certain possible outcome divided by the number of all possible outcomes. Probabilities can be represented as proportions (a number between 0 and 1) or as percentages between 0% and 100%. For any frequency distribution (including the normal curve), the percentage of scores found in a particular region of the distribution (such as between two Z scores) corresponds to the probability of selecting a score from that region. *A sample refers to the relatively small number of instances that are studied in order to make inferences about the larger group from which those instances were drawn. The larger group is known as the population. *Samples are drawn using random selection, a procedure that ensures that each member of a population has an equal chance of being selected. In practice, this technique is usually too difficult or even impossible and social and behavioral researchers use haphazard selection instead. In this case,
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This test prep was uploaded on 04/18/2008 for the course STATISTICS 102 taught by Professor Heredia during the Spring '08 term at TAMU Intl..