STATS EXAM 2 QUESTIONS WITH VERIFIED SOLUTIONS LATEST UPDATE 2026

STATS EXAM 2 QUESTIONS WITH VERIFIED SOLUTIONS LATEST UPDATE 2026 A standard normal table shows the area under the standard normal curve corresponding to any ___ or its fractions. - Answers Z score Suppose that in a particular sample, the mean is 70.07 and the standard deviation is 10.27. What is the raw score associated with a Z score of 1.88? - Answers 89.38 Z score= - Answers (raw score-mean)/standard deviation Raw score= - Answers Mean + (Z score)(standard deviation) What percentage of the area under the normal curve falls between +-3 standard deviations? - Answers 99.72 The normal distribution is central to the theory of ____ statistics. - Answers Inferential SELECT ALL THAT APPLY. Which of the following coincide in a normal distribution? - Answers Mean, Median, and Mode Probability can be calculated as: Number of times an event will occur/Total number of events. - Answers True The normal distribution is a theoretical distribution. - Answers True To find proportion of the area under the normal curve between two Z scores that are both above the mean, it is necessary to examine the - Answers Difference between the areas beyond each Z score A normal distribution represented in Z scores is referred to as a: - Answers normal bell-curve The number of standard deviations that a given raw score is above or below the mean is referred to as a - Answers standard (Z) scores What percentage of the area under the normal curve falls between +-2 standard deviations? - Answers 95.46 What percentage of the area under the normal curve falls between +-1 standard deviations? - Answers 68.26 A normal distribution represented in standard z scores, with - Answers mean=0 and standard deviation=1. Considering the properties of the normal curve, if we know the mean and standard deviation, we are then able to calculate the ___ under the curve between any score and the mean. - Answers area Rare events, with smaller corresponding probabilities, are towards the middle of the normal curve. - Answers False A group that includes all the cases in which a researcher is interested in referred to as a - Answers population A method of sampling that enables researchers to specify for each case in the population the probability of its inclusion in the sample is referred to as ___ sampling. - Answers Probability Which of the following is true about the relationship between the population mean and the mean of the sampling distribution? - Answers uy=uY A theoretical probability distribution of all possible sample values for the statistics in which we are interested in is referred to as a - Answers sampling distribution Which of the following is NOT a parameter? - Answers y When the size of the sample selected from a subgroup is proportional to the size of that subgroup in the entire population, we refer to this as - Answers Proportionate stratified sampling Which of the following is NOT a statistic? - Answers Pi If all possible random samples of size N are drawn from a population with a mean of uY and a standard deviation of oy, then as N becomes larger, the sampling distribution of sample means becomes approximately normal with a mean of uy and a standard deviation of o? This statement is known as the - Answers Central Limit Theorem What is sampling error? - Answers the discrepancy between a sample estimate of a population parameter and the real population parameter Which of the following two qualities are used to calculate the standard error of the mean? - Answers Population standard deviation and sample size SELECT ALL THAT APPLY. Probability - Answers Can be expressed as a proportion Can be expressed as a percentage Can take a maximum value of 1 SELECT ALL THAT APPLY. In a simple random sample - Answers every member of the population has an equal change of being chosen every combination of N members has an equal chance of being chosen Parameter is a measure used to describe the sample distribution. - Answers False 0, 3, 6, 9 is a sample of the population 1, 2, 3, 4, 5, 6, 7, 8, 9, 10. - Answers False In a population of 100 scores, if 20 was our sample size, then using systematic random sample, the value of K is 5. - Answers True ___ is necessary because researchers in the social sciences almost never have enough resources to collect information about the entire set of subjects of interest to the, - Answers Sampling A method of sampling that enables researchers to specify for each case in the population the probability of its inclusion in the sample is referred to as ___ sampling - Answers Probability Which of the following is the notation for the sample mean? - Answers y When the size of the sample selected from a subgroup is proportional to the size of that subgroup in the entire population, we refer to this as - Answers proportionate stratified sampling SELECT ALL THAT APPLY. The central limit theorem tells us that as the sample size gets larger, - Answers the mean of the sampling distribution becomes equal to the population mean the standard error of the mean decreases in size the closer the sample means will be to the population mean