PSYCH 311 4 of 4 WSU
C.) approximately normally distributed
76. Suppose that a researcher selects a sample of participants from a population. If the shape of the distribution in this population is positively skewed, then what is the shape of the sampling distribution of sample means? A) approximately positively skewed B) approximately negatively skewed C) approximately normally distributed D) There is not enough information to answer this question, because the population mean and variance are not given.
C.) Sampling is without replacement
77. For the experimental sampling strategy, A) the order in which a participant is selected matters B) sampling is with replacement C) sampling is without replacement D) participants are not sampled from the population, but instead are sampled from other samples already drawn
B.) Sample Means
78. What values are distributed along the x-axis for a sampling distribution of the sample mean? A) scores B) sample means C) sample variances D) both B and C
C.) Sample Variances
79. What values are distributed along the x-axis for a sampling distribution of the sample variance? A) scores B) sample means C) sample variances D) both B and C
A.) 15
80. A researcher selects a sample of size 4 from a population of size 6. How many possible samples of this size can be selected using experimental sampling? A) 15 B) 30 C) 1,296 D) 4,096
C.) If we select a sample at random, then on average we can expect the sample mean to equal the population mean.
81. What does it mean to say that the sample mean is an unbiased estimator of the population mean? A) The sample means will vary minimally from the population mean. B) The sampling distribution of possible sample means is approximately normally distributed, regardless of the shape of the distribution in the population. C) If we select a sample at random, then on average we can expect the sample mean to equal the population mean. D) all of the above.
A.) equal to the population mean
82. The mean of the sampling distribution of sample means is A) equal to the population mean B) equal to the population variance C) both A and B D) none of the above
D.) 36 and 40
83. A researcher selects a sample of 100 participants from a population with a mean of 38 and a standard deviation of 20. About 68% of the sample means in this sampling distribution should be between a sample mean of A) 34 and 40 B) 34 and 38 C) 38 and 44 D) 36 and 40
C.) 25
84. How many possible samples of size 2 can be selected from a population of 5 using theoretical sampling? A) 5 B) 10 C) 25 D) 32
A.) the probability of A, given that B occurs, and the probability of B, given that A occurs
85. Given two outcomes, A and B, state their relationship as a conditional probability using a "given" statement. (Hint: Be sure to state BOTH possible conditional probabilities).
B.) Central limit
86. The ________________________________________theorem explains that the shape of a sampling distribution of sample means tends toward a normal distribution, regardless of the distribution in the population
A.) Sampling
87. A _______________ distribution of the sample means is a distribution of all possible sample means that can be obtained in samples of a given size (n) from a population (N).
D.) A Coin Flip ( or something with only 2 options)
88. Give an example of two outcomes that are complementary (i.e., their probabilities are complementary.
D.). (given a sufficiently large sample size ... finite level of variance.)
89. Define the central limit theorem.
D.) the formula is ss/df
90. Explain why the sample mean is an unbiased estimator (i.e., what does that mean and how can you check it mathematically?)
B.) mutually exclusive, independent, complementary, and conditional or dependent outcomes.
91. Name the four types of relationships between multiple outcomes.
B.) in text, in a figure (as error bars), or in a table
94. What are three ways that the standard error is reported in research journals?
A.) They have the same probability as positive z scores.
95 Why doesn't the z-table tell you probabilities for negative z-scores?
D.) sees how well a sample mean estimates the population mean
96. Explain what a sampling distribution of the sample mean is.