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    Statistical Inference

    Statistical inference is the process of drawing conclusions or generalizations from the data of interest. Contrary to descriptive statistics, the practice of statistical inference aims to extrapolate from the observed data patterns and explain how the population at large is affected. Generally, a sample of the total population is analyzed and through statistical inference, the larger picture is realized.

    Statistical inference allows the theoretical world and the real world to become connected. The theoretical world consists of the statistical and scientific models being used; the different distributions the samples are taken from; the measures being estimated; and the conclusions being conceived from a statistical view point. On the other hand, the real world parallels the populations being evaluated, from which the samples originate. Statistical inference is the medium through which these two worlds can unite so that observable phenomena can be explained.   

    Often, statistical inference involves the approximation of parameters because the absolute value is unknown. Especially if the distribution being used is in question, an estimation of the unknown distribution is required. In addition to estimating unknown parameters, statistical inference also tries to set confidence or creditable intervals, assume the model type being used, conclude on the hypotheses and classify data points.

    Statistical inferences can be extended beyond the information presented in the data set under investigation. However, it is important that researchers are cautious when constructing these types of generalizations, ensuring that they can be justified and thus, not result in false conclusions. This would be problematic considering that the overall objective of statistical inference is to formulate conclusions and understand the true behaviour of different populations. 

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    BrainMass Categories within Statistical Inference

    Sampling Distribution

    Solutions: 103

    The sampling distribution is a theoretical concept which describes the range of values from which a statistic is likely to be found and the frequency of selecting a particular value.

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    Factor analysis and its assumptions

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    Stevens' four scales of measurement

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    Sample Standard Deviation: Frequency

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    Relationship of T-test and Effect Size

    Can you explain the data what are the assumptions of correlated groups t test provided? 1.What are the assumptions of a correlated groups t test? 2.What measure of effect size is used for a correlated-groups t test? 3.The student decides to conduct the same study using a within-participants design in order to control for di

    Solving and analyzing hypothesis testing question

    Chapter 14 Chapter 14 ( total 10 points = part I and part II) 2. A member of the state legislature has expressed concern about the differences in the mathematics test scores of high school freshmen across the state. She asks her research assistant to conduct a study to investigate what factors could account for the differences.


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    Statistics - Chi-Square and Contingency Tables

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    Understanding a Published Study

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    Inferential Statistic: T Test

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    Inferential Statistics Using T-Test

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    Scheduling New Workers, Choosing a New Work Schedule

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    Forecasting using Excel

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    Statistical Inference Problem Set

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    Statistics: Type I and Type II Error Analysis

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    Statistical inference to business decision scenarios

    The manager of the Gander Mountain store in Frogtown, IL, believes that his prices for ammunition are lower than the prices of his primary competitor in the hunting equipment market, Cabela's. He would like to be able to provide evidence to support this assertion. -What are the Gander Mountain manager's null and alternative h

    Analyze business decision opportunities using basic inferential statistics

    use the Sample Size Estimator In the early years of the twenty-first century, annual salaries for federal employees in the Upper Midwest averaged approximately $42,000, with a population standard deviation (?) of $4,900. If we drew a random sample of 25 federal employees from this population: What would the standard e

    Inferences from Dependent Samples in Disney movies for alcohol

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    Importance of Statistical Theory in Business Decision Making

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    Inference about population mean

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    Statistics - Inference about a population mean

    The placebo effect. The placebo effect is particularly strong in patients with Parkinson's disease. To understand the workings of the placebo effect, scientists measure activity at a key point in the brain when patients receive a placebo that they think is an active drug and also when no treatment is given. The same six patie

    Inference about a population mean

    Calcium and blood pressure. In a randomized comparative experiment on the effect of calcium in the diet on blood pressure, researchers divided 54 healthy white males at random into two groups. One group received calcium; the other, a placebo. At the beginning of the study, the researchers measured many variables on the subjects.


    Deliverable Length: 2 pages Details: Using AIU's large database of survey responses from the AIU data set, complete the following: Perform hypothesis testing on one variable's data. (Choose either the intrinsic or extrinsic column.) Perform a t-test by formulating a null and an alternative statement, choosing an acceptab

    Hypothesis Testing - Based on your readings in the white papers, text and lectures, how do you feel that the inferential statistical technique of Hypothesis Testing can be used by managers to make better business decisions? How does or can your organization use this statistics concept as it conducts business research and makes decisions?

    Based on your readings in the white papers, text and lectures, how do you feel that the inferential statistical technique of Hypothesis Testing can be used by managers to make better business decisions? How does or can your organization use this statistics concept as it conducts business research and makes decisions?

    Simple Statistics Problems - Problem 3-77 Suppose that 5 of a total of 20 company accounts are in error. An auditor selects a random sample of 5 out of the 20 accounts. Let X be the number of accounts in the sample that are in error. Is X binomial? If not, what distribution ... [See the Attached Questions File.]

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    Drawing Inferences from Large Samples

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    Statistical Inference

    An agribusiness company currently uses one brand of commercial fertilizer. However, a new fertilizer is available that the manufacturer says will produce higher than average crop yields. Name the basic category of statistical inference tools the manufacturer would use to provide this information. Describe a hypothesis upon