Sample Final(modified) - Statistics

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44) Consider a continuous random variable X=length of time (in hours) of a flight from SF to NY and suppose it has adistribution that looks like the following:The probability that a flight from SF to NY will be longer than 3.5 hours is 0.875.45) A histogram is a graphical display of one quantitative variable.46) For a discrete random variable X, P(X > 2) = P(X ≥ 2).47) In a room that contains 5 people, the probability that at least 2 of them have the same birthday is 0.548) The experiment consists of tossing 5 unbiased coins simultaneously. The number of outcomes in this experimentis 5.49) A numerical measure describing a sample is called a statistic.50) In a family of 3 children, the probability that exactly 2 of them are girls is 0.25.51) If a random sample is of size n ≥ 30, or if the original population is normally distributed, the distribution of thesample means has a normal distribution.52) An interval of numbers containing the most believable values for a parameter is called the confidence interval.53) When the degrees of freedom are small, t-distribution is slightly skewed.54) P-value is the probability that the test statistic equals the observed value or a value even more extreme, when thenull hypothesis is true.55) When performing the hypothesis test regarding population proportion, the assumption that np 0 ≥ 15 and n(1-p 0 ) ≥15 are required so that the sampling distribution of the sample proportion is normal.6
56) A test statistic is a quantity that is far away from zero when Ho is true and that is close to zero if Ha is true.57) If the null hypothesis is true but the test concluded with “do not reject null hypothesis”, then a Type II error ismade.58) The 95% confidence interval for the population proportion of voters supporting the bill is (0.78, 0.86). It isreasonable to expect to observe the proportion of voters supporting the bill to be p = 0.70.59) When the alternative hypothesis is two-sided, the null hypothesis is rejected for values of the test statistics locatedin either tail of that statistic’s sampling distribution.60) Degrees of freedom are equal to the difference between the 2 sample sizes.7
Page 5: 35) Find the p-value for a 2-tailed

Sample Final(modified) - Statistics

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