PSYC 354 QUIZ 2 COMPREHENSIVE EXAMINATION ON MEASURES OF CENTRAL TENDENCY – COVERING CALCULATION, SELECTION CRITERIA BY MEASUREMENT SCALE (NOMINAL, ORDINAL, INTERVAL, RATIO), DISTRIBUTION SHAPE (SYMMETRICAL VS. SKEWED), AND PROPERTIES OF RESISTANT VS. NON

PSYC 354 QUIZ 2 COMPREHENSIVE EXAMINATION ON MEASURES OF CENTRAL TENDENCY – COVERING CALCULATION, SELECTION CRITERIA BY MEASUREMENT SCALE (NOMINAL, ORDINAL, INTERVAL, RATIO), DISTRIBUTION SHAPE (SYMMETRICAL VS. SKEWED), AND PROPERTIES OF RESISTANT VS. NON-RESISTANT ESTIMATORS Question 1 What is the most appropriate measure of central tendency for data measured on a nominal scale? A) Mean B) Median C) Mode D) Mode Rationale: The mode is the only measure of central tendency appropriate for nominal data because nominal data consists of categories without numerical order, making mean and median impossible to calculate meaningfully. ________________________________________ Question 2 In a positively skewed distribution, which measure of central tendency is typically the largest? A) Median B) Mode C) Mean D) All are equal Rationale: In a positively skewed distribution, the mean is pulled toward the tail (higher values) and is therefore larger than the median, which is larger than the mode. ________________________________________ Question 3 What is the median of the following scores: 2, 4, 6, 8, 10, 12? A) 6 B) 7 C) 7 D) 8 Rationale: With an even number of scores (n=6), the median is the average of the two middle scores: (6+8)/2 = 7. ________________________________________ Question 4 A distribution has a mean of 50 and a median of 45. This distribution is most likely: A) Symmetrical B) Positively skewed C) Negatively skewed D) Bimodal Rationale: When the mean is greater than the median, the distribution is positively skewed (skewed to the right) because the mean is pulled toward higher values. ________________________________________ Question 5 Which measure of central tendency is most affected by extreme scores? A) Mode B) Median C) Mean D) Range Rationale: The mean is the most sensitive to extreme scores because it uses all values in its calculation, making it pull toward outliers. ________________________________________ Question 6 For the following scores: 3, 5, 5, 7, 9, 9, 9, 11, what is the mode? A) 7 B) 8 C) 9 D) No mode exists Rationale: The mode is the score that occurs most frequently. The score 9 appears three times, more than any other value. ________________________________________ Question 7 Which measure of central tendency divides a distribution exactly in half? A) Mean B) Median C) Mode D) Standard deviation Rationale: The median is defined as the value that divides a distribution into two equal halves, with 50% of scores above and 50% below. ________________________________________ Question 8 A researcher measures anxiety levels on an interval scale. Which measure of central tendency should be used if the distribution is normal? A) Mean B) Median C) Mode D) Any of the above Rationale: In a normal distribution, the mean is the preferred measure because it uses all data points and provides the most accurate representation of central tendency. ________________________________________ Question 9 If a distribution is perfectly symmetrical, which relationship is true? A) Mean Median Mode B) Mean Median Mode C) Mean = Median = Mode D) Mean = Mode, but Median differs Rationale: In a perfectly symmetrical distribution, all three measures of central tendency are equal at the center point. ________________________________________ Question 10 What is the mean of the following scores: 5, 10, 15, 20, 25? A) 10 B) 15 C) 20 D) 25 Rationale: The mean is calculated by summing all scores and dividing by the number of scores: (5+10+15+20+25)/5 = 75/5 = 15. ________________________________________ Question 11 A distribution has two modes. This distribution is called: A) Symmetrical B) Skewed C) Bimodal D) Normal Rationale: A distribution with two distinct modes is called bimodal, indicating two peaks in the frequency distribution.