Sampling Distributions Sampling Error = x̄ - μ Z-Values for a sampling distribution of x̄ : Z = Z-Values adjusted with Finite Population Correction Applied if: the sample is large relative to the population (n is greater than 5% of N) and sampling Is without replacement Z = Using the Sampling Distribution for Means Compute the Sample Mean Define the sampling distribution μx̄ = Define the probability statement of interest P(z30 will give sampling distribution that is nearly normal fairly
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0.03. What is the minimum sample size that the company should use for surveying the driving route preferences of Electronics City employees in order to achieve the above desired level of precision in the proportion estimate? Question 3: [4 marks] Two research laboratories have independently produced drugs that provide relief to arthritis sufferers. The first drug was tested on a group of 90 arthritis sufferers and produced an average of 8.5 hours of relief‚ and a sample standard deviation of 1.8
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of sample size • The concept of saturation point Keywords: accidental sampling‚ cluster sampling‚ data saturation point‚ disproportionate sampling‚ equal and independent‚ estimate‚ information-rich‚ judgemental sampling‚ multi-stage cluster sampling‚ non-random sample‚ population mean‚ population parameters‚ quota sampling‚ random numbers‚ random sample‚ sample statistics‚ sampling‚ sampling design‚ sampling element‚ sampling error‚ sampling frame‚ sampling population‚ sampling unit‚ sample size
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A statistics practitioner took a random sample of 50 observations from a population with a standard deviation of 25 and computed the sample mean to be 100. a.Use an interval estimate to estimate the population mean with 90% confidence.[mu-1.64*SD/√n‚mu+1.64*SD/√n] [100-1.64*25/√50‚100+1.64*25/√50][94.2017‚105.7983]-90% Confidence b.95% confidence. [mu-1.96*SD/√n‚mu+1.96*SD/√n] [100-1.96*25/√50‚100+1.96*25/√50][93.0704‚106.9296]-95% Confidence c.99% confidence. [mu-2.57*SD/√n‚mu+2.57*SD/√n] [100-2
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price and age  second hand price and mileage  second hand price and engine size 6. Cumulative Frequency 18-35  1st set second hand prices of the sample of 40 cars and individual car makes  2nd set age of the sample of 40 cars and individual car makes  3rd set mileage of the sample of 40 cars and individual car makes  4th set engine size of the sample of 40 cars and individual car makes 7. Box and whisker plots 35-41  1st set-
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HYPOTHESIS TESTING PROBLEM 1 A certain brand of fluorescent light tube was advertised as having an effective life span before burning out of 4000 hours. A random sample of 84 bulbs was burned out with a mean illumination life span of 1870 hours and with a sample standard deviation of 90 hours. Construct a 95 confidence interval based on this sample and be sure to interpret this interval. Answer Since population standard deviation is unknown‚ t distribution can be used construct the confidence
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lesser than TT Air during each 24-hour period i.e. (10.229-7.167=3.062). • The sample size of AA Fly (27) is lesser than TT Air (28). Even though AA Fly’s sample is 1 day shorter than TT Air‚ it does not significantly affect the output as the one day does not change much (unless there had been a market shock). However based on Central Limit Theorem‚ if the sample size is greater than or equal to 30 samples‚ the sample statistics reflect the time population parameters. • The Median data does not
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revenue occurred on the 88th day for both outlets. The lowest revenue occurred on 39th day for both outlets. Generally‚ both outlets earn roughly the same amount of revenue each day. 2a. Confidence interval is a range of values constructed from sample data so that the population parameter is likely to occur within that range at a specific probability (Lind‚ Marchal & Wathen‚ 2013). Using the 95% level of confidence‚ the confidence interval for Unicafe West is 220.42 6.211. The confidence
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Ch11 case Golf 1. is mean driving distances of current balls is mean driving distances of new balls is mean driving distances of sampled current balls is mean driving distances of sampled new balls Use the test statistics and normal distribution table to get p-value. If p-value is smaller than‚ then we reject H0‚ which means the mean driving distances of current balls and new balls are different. 2. From the t distribution table we find that p-value is between 0.05 and 0
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useful as well as valuable. Two of the limitations I encountered on when evaluating my survey my small sample size and the location where I decided to carry out my survey. My sample size‚ consisting of 20 participants‚ was too small to be able represent the target market segment aged 16 – 18. “A small sample size may result in the lack of statistical representation” ‚ as a smaller sample sizes get increasingly further away from the entire population. In reality there is simply not enough; time‚ energy
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