Statistics in Business QNT/351 Donald Lifke Statistics in Business Statistics is defined as the science of data. It involves collecting‚ classifying‚ summarizing‚ organizing‚ analyzing‚ and interpreting numerical information. (McClave‚ Benson‚ & Sincich‚ 2011‚ p. 3). . There are two different application process involved in statistics; descriptive and inferential. Descriptive statistics is the analysis that helps describe‚ summarize or show data in a way to allow patterns to emerge
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1) What is the difference between probability distributions and frequency distributions? Provide an example that demonstrates the difference between the two. A probability distribution directly corresponds to a frequency distribution‚ except that it is based on theory (probability theory)‚ rather than on what is observed in the real world (empirical data). A frequency distribution is based on actual observations. An example would be observing a coin be flipped twenty times. A probability distribution
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Rebecca Verian 2577648 Context: π 1: There is no significant difference between the mean heights of the singers. π2: The average of heights of high pitched voices is equal. π3: The average of heights of low pitched voices is equal. Conditions: * There are 39 cases. * Based on the graph gotten the average heights of Soprano are 64.25 inches. * The average heights of the Alto singers are 64.88 inches. * The Tenor singers had an average height of 69.15 inches. * The mean
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Key Synthesis/Potential Test Questions (PTQs) • What is statistics? Making an inference about a population from a sample. • What is the logic that allows you to be 95% confident that the confidence interval contains the population parameter? We know from the CLT that sample means are normally distributed around the real population mean (). Any time you have a sample mean within E (margin of error) of then the confidence interval will contain . Since 95% of the sample means are within E
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1. STAT10T 7.2.1-2 (Points: 5.0) Solve the problem. Find the critical value zα/2 that corresponds to a degree of confidence of 91%. a. 1.645 b. 1.75 c. 1.34 d. 1.70 2. STAT10T 7.2.3-2 (Points: 5.0) Solve the problem. The following confidence interval is obtained for a population proportion‚ p: 0.817 < p < 0.855 Use these confidence interval limits to find the point estimate‚ . a. 0.833 b. 0.817 c. 0.839 d. 0.836 3. STAT10T 7.2.4-3 (Points: 5
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evidence to infer that the population mean is not equal to 180. c t x s/ n 175 180 60 / 200 1.18‚ p-value = .2400. There is not enough evidence to infer that the population mean is not equal to 180. 269 d. As the s increases‚ the test statistic increases and the p-value increases. 12.12 H0 : H0 : = 50 50 a Rejection region: t t x s/ n 52 50 15 / 25 t / 2‚n 1 t .05‚24 1.711 or t t / 2‚n 1 t .05‚24 1.711 .67‚ p-value = .5113. There is not enough evidence
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There are several types of bad statistics that can be seen when looking at statistical data. According to the video “Don’t be fooled by bad statistics” (2010)‚ there are three basic types of bad data consisting of poorly collected data‚ leading questions‚ and misuse of center. Poorly collected data can produce misleading results. For example‚ when a publishing company conducted a phone survey of popular magazines but did so during business hours when stay at home moms were most likely to participate
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45.16 + 2.3263 * 10 = 99% of households spent less than $68.42 NORMINV (.99‚ 45.16) References Levine‚ D.‚ Stephan‚ D.‚ Krehbiel‚ T.‚ & Berenson‚ M. (2008) Statistics for managers using Microsoft Excel w/cd. (5th ed.). Upper Saddle River‚
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It is known that there are two data types that are utilized to evaluate and draw meaningful conclusions through statistics‚ population and sample data. These two data types are utilized to formulate end conclusions of data that is to be collected and data that is to be reviewed. The description of population data can best be explained‚ as the complete collection of all data that is to be queried/collected and reviewed. Sample data‚ a subset of population data‚ is the partial collection and review
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CHAPTER 10: TWO-SAMPLE TESTS WITH NUMERICAL DATA 1. The t test for the difference between the means of 2 independent populations assumes that the respective a) sample sizes are equal. b) sample variances are equal. c) populations are approximately normal. d) all of the above ANSWER: c TYPE: MC DIFFICULTY: Moderate KEYWORDS: pooled-variance t test‚ assumption 2. The t test for the mean difference between 2 related populations
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