# Phc 4069-A Distribution Of Sample Means Is A Collection Of Sample

Question 11 ptsA distribution of sample means is a collection of samplemeans fromsamples of different sizes from different populations. samples of size N from different populations. samples of size N from the same population. samples of different sizes from the same populationQuestion 21 ptsA friend of mine studies the effects of praise on happiness. She believes that children who receive praise are happieroverall than children who do not receive praise. Shemeasures happiness by counting the number of times a childsmiles in a one hour period. She knows that in the populationof children who do not receive praise smiles average 4 timesper hour with a standard deviation of . 5, and that these dataare normally distributed. She selects a sample of 100children whom she knows receive praise and finds that theysmile an average of 3. 5 times per hour. The characteristics ofthe appropriate comparison (sampling) distribution area mean of zero and a standard deviation of 1. a mean of 4 and a standard deviation of . 5. a mean of 4 and a standard deviation of . 05. a mean of 3. 5 and a standard deviation of . 5. Question 31 ptsThe normal approximation to the binomial distribution ismost useful for finding which of the following?The probability P(X = 5) when X is a binomialrandom variable with large nThe probability P(X 5) when X is a binomialrandom variable with large n. The probability P(X = 5) when X is a normal randomvariable with small nThe probability P(X 5) when X is a normal randomvariable with small nQuestion 41 ptsThe central limit theorem tells us that the samplingdistribution of the sample mean is approximately normal. Which of the following conditions are necessary for thetheorem to be valid: a) The sample size has to be large. b) We have to be sampling from a normalpopulation. c) The population has to be symmetric. d) Both a) and c). Question 51 ptsThe Central Limit Theorem is important in statistics becausea) for a large sample size n, it says the population isapproximately normalb) for any population, it says the sampling distributionof the sample mean is approximately normal,regardless of the sample size. c) for a large sample size n, it says the samplingdistribution of the sample mean is approximatelynormal, regardless of the shape of the populationd) both a) and c). above. Question 61 ptsThe standard error of the proportion p will become largeras p approaches 0. as p approaches . 50. as p approaches 1. 00. as n increases. Question 71 ptsSince the sample size is always smaller than the size of thepopulation, the sample meanmust always be smaller than the population meanmust be larger than the population meanmust be equal to the population meancan be smaller, larger, or equal to the populationmeanQuestion 81 ptsA simple random sample from an infinite populationis a sample selected such thateach element is selected independently and fromthe same populationeach element has a 0. 5 probability of beingselectedeach element has a probability of at least 0. 5 ofbeing selectedthe probability of being selected changesQuestion 91 ptsIf we consider the simple random sampling process as anexperiment, the sample mean isalways zeroalways smaller than the population meana random variableexactly equal to the population meanQuestion 101 ptsAs the sample size becomes larger, the sampling distributionof sample mean approaches abinomial distributioneither binomial distribution or normaldistributionnormal distributionnone of the above