ALL of the following questions by selecting the most correct answer and writing down the corresponding letter. 1. Organizing a set of scores into a table or a graph would be an example of using ______. a. population statistics b. sample statistics c. descriptive statistics d. inferential statistics 2. In a correlational study ... a. 1 variable is measured and 2 groups are compared b. 2 variables are measured and 2 groups are compared c. 1 variable is measured and there is only 1 group of participants d. 2 variables are measured and there is only 1 group of participants 3. Kevin is interested in investigating the influence of intelligence on the ability to solve novel problems. If Kevin does not account for variables such as age, which could also influence the ability to solve novel problems, age could be considered a (n) ____________ variable. a. Random b. Dependent c. Confounding d. Problematic 4. Which of the following accurately describes the proportions in the tails of a normal distribution? a. Proportions in the right-hand tail are positive, and proportions in the left-hand tail are negative. b. Proportions in the right-hand tail are negative, and proportions in the left-hand tail are positive. c. Proportions in both tails are positive. d. Proportions in both tails are negative. 5. A random sample of n = 60 scores is selected from a population. In which of the following scenarios will a normal distribution be more likely? a. When the scores in the sample will form a normal distribution. b. When the scores in the population form a normal distribution. c. When the distribution of sample means form a normal distribution. d. None of the distributions (the sample, population, or distribution of sample means) will definitely be normal. 6. What is the standard error of M? a. The sample mean b. The sample standard deviation c. The mean of the distribution of sample means d. The standard deviation of the distribution of sample means. For each of the following statements, indicate whether they are true or false. If false, provide a reason why it is false/or what the correct answer is where applicable. 1. In the experimental method, the researcher uses purposive sampling in allocating participants to control or experimental groups? 2. In a correlational study, the researcher manipulates one variables to examine the impact on another variable. 3. The goal for an experiment is to demonstrate the association of two variables whilst minimizing or holding other variables constant. 4. The SA Electoral Commission records the gender, race, residential address, ID number, age and name of each voter in SA. The Commission is measuring discrete variable(s). 5. A set of scores ranges from a low of X = 18 to a high of X = 59. If the scores are put in a grouped frequency distribution table with an interval width of 5 points, the bottom interval should be 18-23. Answer ALL of the following questions. 1. Explain why it is necessary to have more than one standard procedure for defining and measuring central tendency. 2. The purpose of variability is to measure and describe the degree to which the scores in a distribution are spread out or clustered together. Name and provide a description of the three basic measures of variability. 3. By using an example, explain what random sampling entails. 4. By using an example, explain why standardised distributions (z-scores) are used in research. 5. Describe what happens to the mean, the standard deviation, and the shape of a distribution when all of the scores are transformed into z-scores. 6. By using an example, explain how statistical analysis of samples helps us draw conclusions about populations, as well as why it is necessary to make use of samples