Which of the following statements are correct? a.Positively skewed distributions have a tail to the right; negatively skewed distributions have a tail to the left. b.A variable cannot be both skewed and kurtotic. c.The sampling distribution of means is calculated by taking data from multiple samples across a population. d.The standard error of the mean is just another way of describing the standard deviation and variance. e.Type I and Type II errors are inversions - as you increase your risk of one, you decrease your risk of the other. f.Point estimates are more accurate than confidence intervals.

Which of the following statements are correct? a.A correlation p-value of 0.05 means there is a 5% probability that the findings represent a meaningful relationship between the variables. b.The third variable problem is when an extra unmeasured variable influences both variables in the correlation. c.The correlations r = 0.395 and r = -0.410 are both moderate in size. d.A negative correlation means that as one variable decreases, the other also decreases. e.As long as the variables are time ordered, then a correlation can be used to establish causation. f.Correlation statistics are more accurate when two variables have a linear relationship, rather than a curvilinear one.

Which of the following statements are INCORRECT? a.Secondary data can have issues with reliability and validity if the data were originally collected for a different purpose. b.When reporting findings back to organisations, you should never report numerical statistics. c.If we have a large enough sample size, inferential statistics enable us to make accurate inferences about our sample based on known characteristics of the population. d.Calculating a confidence interval for a mean value tells you how confident you can be about the accuracy of that mean. e.Correlation is pretty much the same thing as causation. f.The degrees of freedom statistic varies across statistical tests, depending on the particular model that is being tested.

Which of the following statements are correct? a.A negative t statistic means that the difference between the groups is small. b.A t-test p-value of 0.002 means there is a 98% probability that the findings represent a meaningful difference between the variables. c.Once we have a significant effect, the size of the difference matters very little. d.A t-test assesses whether the mean difference between the paired scores is equal to zero. e.A significant t-test p-value suggests we can be confident that the mean at Time 2 is greater than the mean at Time 1. f.If we don't have independence of observations, the t-test results may be inaccurate or distorted.

Which of the following statements are INCORRECT? a.Academic reports typically reference existing theory and literature; non-academic reports typically do not. b.P-values of < .001 demonstrate a more important effect than p-values of < .05. c.A Type I error means you have found an effect when no real effect exists. d.Longitudinal designs are more resource intensive than cross-sectional designs due to the need to collect repeated data over time from the same participants. e.Quasi-experiments are a type of experiment that take place in a less controlled setting. f.A measure can be reliable but not valid.