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Exploratory Data Analysis

Decent Essays

1. 1 Displaying Distributions with Graphs 1. In statistics, individuals are the objects described by a set of data, they can be people or animal or things. 2. In statistics, a variable is any characteristic of an individual. A variable can take different values for different individuals. 3. Exploratory data analysis is an examination where statistical tools and ideas can help you examine data in order to describe their main features. 4. A categorical variable places an individual into one of several groups or categories while a quantitative variable takes numerical values for which arithmetic operations such as adding and averaging make sense. 5. It is useful to use a bar chart when dealing with counts 6. It is useful to use a pie chart when …show more content…

The median is resistant to extreme observations because its based on the middle one or two observations of the ordered list, while the mean is nonresistant due to the influence of few extreme observations. 5. In stats, spread is a way to measure the variability of the observations around the center. 6. To calculate Q1 and Q3 , you must first arrange the observations in increasing order to find the median, Q1 is the median of the observations whose position in the list is to the left of the overall median, Q3 is the median of the observations whose position in the list is to the right of the overall median. 7. The five-number summary is minimum, Q1, median, Q3, maximum 8. Standard deviation measures spread. 9. The relationship between variance and standard deviation is that the standard deviation(s) is the square root of the variance s2. 10. Standard deviation equals zero when there is no spread, that only happens when all observations have the same value. 11. Standard deviation is non resistant to extreme observations because strong skewness or a few outliers can make the standard deviation very large. 2.1 Density Curves and the Normal Distributions A density curve is a curve that is always above or on the x-axis and one that has its area exactly one underneath that

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