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What are the differences between Mean and Median?

Mean: Sensitive to outliers, best for symmetric data | Median: Resistant to outliers, best for skewed data.

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What are the differences between Mean and Median?
Mean: Sensitive to outliers, best for symmetric data | Median: Resistant to outliers, best for skewed data.
What are the differences between Standard Deviation and IQR?
Standard Deviation: Measures spread using all data, sensitive to outliers | IQR: Measures spread of middle 50%, resistant to outliers.
What are the differences between Parameters and Statistics?
Parameters: Describe populations, usually unknown | Statistics: Describe samples, used to estimate parameters.
What are the differences between resistant and nonresistant measures?
Resistant: Not affected by outliers, e.g., median, IQR | Nonresistant: Affected by outliers, e.g., mean, standard deviation.
What are the differences between using the 1.5 x IQR rule and standard deviations method for identifying outliers?
1. 5 x IQR: Based on quartiles, resistant to extreme values | Standard Deviations: Based on mean and standard deviation, sensitive to extreme values.
What is the definition of 'Mean'?
The average value, calculated by summing all values and dividing by the number of values.
What is the definition of 'Median'?
The middle value when data is ordered. If there's an even number of data points, it's the average of the two middle values.
What is the definition of 'Standard Deviation'?
A measure of how much individual data points vary from the mean.
What is the definition of 'IQR'?
The interquartile range, representing the range of the middle 50% of the data (Q3 - Q1).
What are outliers?
Data points that are unusually far from the rest of the data.
Explain the concept of 'resistance' in statistics.
Resistance refers to a statistic's sensitivity to outliers. Resistant statistics are not greatly affected by extreme values.
Explain why we use n-1 in the sample standard deviation formula.
We subtract 1 from 'n' (degrees of freedom) when calculating the sample standard deviation to make it a better estimator of the population standard deviation.
Explain how the shape of a distribution affects the relationship between the mean and median.
In a symmetric distribution, the mean and median are approximately equal. In a right-skewed distribution, the mean is greater than the median. In a left-skewed distribution, the mean is less than the median.
Explain the meaning of quartiles.
Quartiles divide a dataset into four equal parts. Q1 is the 25th percentile, Q2 (median) is the 50th percentile, and Q3 is the 75th percentile.
Explain when it is appropriate to use the mean as a measure of center.
The mean is most appropriate for symmetric distributions without significant outliers, as it uses all data points and reflects the overall trend.