All flashcards
Flashcard 1: What is the purpose of a stem-and-leaf plot?
Answer: It displays quantitative data to show distribution details. Separates tens and ones digits clearly.
Flashcard 2: Describe a positively skewed distribution.
Answer: Positively skewed: tail extends to the right. Most data on left, few high values.
Flashcard 3: Calculate the range: 12, 7, 19, 5, 10.
Answer: Range = 14. 19−5=14
Flashcard 4: State the formula for the z-score of a data point.
Answer: z=standard deviationx−mean. Standardizes distance from mean in units.
Flashcard 5: What is the formula for the mean of a data set?
Answer: Mean=n∑xi. Sum all values, divide by count.
Flashcard 6: Identify the measure of central tendency least affected by outliers.
Answer: The median is least affected by outliers. Extreme values don't shift median much.
Flashcard 7: What is the mean of the data set: 4, 8, 6, 10, 2?
Answer: The mean is 6. Sum all values (30) and divide by count (5).
Flashcard 8: What is the median of the data set: 3, 7, 9, 2, 4?
Answer: The median is 4. Middle value when ordered: 2, 3, 4, 7, 9.
Flashcard 9: Identify the shape of a distribution with a long right tail.
Answer: The shape is right-skewed. Long tail extends toward higher values on the right.
Flashcard 10: What is the median of the data set: 3, 7, 9, 2, 4?
Answer: The median is 4. Middle value when ordered: 2, 3, 4, 7, 9.
Flashcard 11: Identify the shape of a symmetric distribution.
Answer: A symmetric distribution is mirrored around its center. Both sides look identical when folded.
Flashcard 12: What does the standard deviation measure?
Answer: The standard deviation measures data spread around the mean. Shows how far values deviate from center.
Flashcard 13: How is range calculated in a data set?
Answer: Range = Maximum value - Minimum value. Subtract smallest from largest value.
Flashcard 14: Identify the best measure of center for skewed data.
Answer: The median is the best measure for skewed data. Outliers don't affect median much.
Flashcard 15: What is the mean of the data set: 4, 8, 6, 10, 2?
Answer: The mean is 6. Sum all values (30) and divide by count (5).
Flashcard 16: Which measure of center is most affected by outliers?
Answer: The mean is most affected. Outliers pull the mean toward extreme values.
Flashcard 17: Identify the shape of a distribution with a long right tail.
Answer: The shape is right-skewed. Long tail extends toward higher values on the right.
Flashcard 18: Find the mean: 4, 8, 6, 5.
Answer: Mean = 5.75. (4+8+6+5)÷4=5.75
Flashcard 19: Find the standard deviation: data set 4, 4, 5, 5.
Answer: Standard deviation = 0.5. Mean is 4.5, deviations squared and averaged.
Flashcard 20: What is a bimodal distribution?
Answer: A distribution with two distinct peaks or modes. Two separate frequency peaks exist.
Flashcard 21: What is the interquartile range (IQR)?
Answer: IQR = Q3 - Q1. Third quartile minus first quartile.
Flashcard 22: What does the term 'spread of data' refer to?
Answer: It refers to the variability or dispersion of data points. How scattered data points are.
Flashcard 23: What is the mode of a data set?
Answer: The mode is the most frequently occurring value. Count frequency of each value.
Flashcard 24: What are quartiles?
Answer: Quartiles divide data into four equal parts. 25%, 50%, 75% split points.
Flashcard 25: What is a cumulative frequency graph?
Answer: It shows cumulative totals of data points up to each class. Running total increases at each point.
Flashcard 26: Identify the effect of skewness on mean and median.
Answer: In skewed data, mean is pulled toward the tail. Median stays centered, mean shifts.
Flashcard 27: What does a scatter plot show?
Answer: A scatter plot shows the relationship between two variables. Points reveal correlation patterns.
Flashcard 28: What is a histogram used for?
Answer: A histogram displays the frequency distribution of data. Bars show count in each interval.
Flashcard 29: What does the skewness of a distribution indicate?
Answer: Skewness indicates the asymmetry of a distribution. Measures if distribution leans left or right.
Flashcard 30: Describe a negatively skewed distribution.
Answer: Negatively skewed: tail extends to the left. Most data on right, few low values.