1) Suppose that an independent laboratory has tested trash bags and has found that no 30-gallon bags that are currently on the market have a mean breaking strength of 50 pounds or more. On the basis of these results, the producer of the new, improved trash bag feels sure that its 30-gallon bag will be the strongest such bag on the market if the new trash bag's mean breaking strength can be shown to be at least 50 pounds. The mean of the sample of 40 trash bag breaking strengths in Table 1.9 is x=50.575. If we let u denote the mean of the breaking strengths of all trash bags of the new type and assume that o equals 1.65:

a. Calculate 95 percent and 99 percent confidence intervals for u. b. Using the 95 percent confidence interval, can we be 95 percent confident that u is at least 50 pounds? Explain c. Using the 99% confidence interval, can we be 99% confident that u is at least 50 pounds? explain d. Based on your answers to parts b and c, how convinced are you that the new 30-gallon trash bag is the strongest such bag on the market?

(a) (i) 95% confidence interval for μ:n = 40x-bar = 50.575s = 1.65% = 95Standard Error, SE = σ/Ön = 0.2609z- score = 1.9600Width of the confidence interval = z * SE = 0.5113Lower Limit of the confidence interval = x-bar - width = 50.0637Upper Limit of the confidence interval = x-bar + width = 51.0863The confidence interval is [50.0637 pounds, 51.0863 pounds](ii) 99% confidence interval for μ:n = 40x-bar = 50.575s = 1.65% = 99Standard Error, SE = σ/Ön = 0.2609z- score = 2.5758Width of the confidence interval = z * SE = 0.6720Lower Limit of the confidence interval = x-bar - width = 49.9030Upper Limit of the confidence interval = x-bar + width = 51.2470The confidence interval is [49.9030 pounds, 51.2470 pounds](b) Yes, we can be 95% confident that μ is at least 50 pounds, since the entire 95% confidence interval lies above 50 pounds (c) No, we can’t be 99% confident that μ is at least 50...

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BUS 308 STATISTICS FOR AMANAGERS
BUS 308 Week 1 DQ 1 Language
Numbers and measurements are the language of business.. Organizations look at results, expenses, quality levels, efficiencies, time, costs, etc. What measures does your department keep track of ? How are the measures collected, and how are they summarized/described? How are they used in making decisions? (Note: If you do not have a job where measures are available to you, ask someone you know for...

...Statistics Cheat Sheet
Proportion = Frequency x 100 = Percentage Total No | Z score (standardised value)-how many sds from the mean the value liesZ score = data value – mean Standard deviation | Metric Data = ExploreCategory = Frequencies |
Bigger sample size will give a narrower confidence interval range (more specific) outliers affect the mean but not the median – this is why the median is preferred here.mean | |...

...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...

...G036
* Yes because the p-value is less than 0.05 or No, because the p-value is greater than 0.05
* The coefficient of variation is the standard deviation of a data set, divided by the mean of the same data set.
* Z score = x -ms
* The Independent part is what you, the experimenter, changes or enacts in order to do your experiment. The dependent variable is what changes when the independent variable changes - the dependent variable depends on the outcome of the...

...Intervals
First you have to know three things:
Statistical inference: the process of using sample statistics to estimate population parameters.
Confidence level: the probability that a population parameter lies within a given confidence interval
Confidence interval: the range of values in which the population parameter is estimated to fall.
A statistic is an estimate of a parameter
But the statistic will rarely equal the parameter...

...Statistics 1
Business Statistics
LaSaundra H. – Lancaster
BUS 308 Statistics for Managers
Instructor Nicole Rodieck
3/2/2014
Statistics 2
When we hear about business statistics, when think about the decisions that a manager makes to help make his/her business successful. But do we really know what it takes to run a business on a statistical level? While some may think that business...

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MBA 501A – [STATISTICS]
ASSIGNMENT 4
INSTRUCTIONS: You are to work independently on this assignment. The total number of points possible is 50. Please note that point allocation varies per question. Use the Help feature in MINITAB 16 to read descriptions for the data sets so that you can make meaningful comments.
[10 pts] 1. Use the data set OPENHOUSE.MTW in the Student14 folder. Perform the Chi
Square test for independence to determine whether style of home and...

...alternative hypothesis should state µ1 − µ2 > 0 ANSWER: c
2.
A Type I error is committed when a. a true alternative hypothesis is not accepted b. a true null hypothesis is rejected c. the critical value is greater than the value of the test statistic d. sample data contradict the null hypothesis ANSWER: b In determining an interval estimate of a population mean when σ is unknown, we use a t distribution with a. n − 1 degrees of freedom
3.
b. c. d. ANSWER: 4.
n...