Centrality measures

The primary purpose of descriptive statistics is to provide a summary of the data. Descriptive statistics might prove useful if you need to quickly get a grasp of the data at hand during the interview.

The most recognized types of descriptive statistics are measures of central tendency, also known as centrality measures.

In this exercise, you will work with the cats dataset from the MASS package. The cats dataset contains the following variables:

Sex - sex,
Bwt - body weight, and
Hwt - heart weight

of domestic cats.

By calculating central tendency measures, you'll be able to answer questions about the skewness of the data.

Recall the relationship between the mean and the median in skewed distributions:

The dataset has been preloaded as cats.

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Practicing Statistics Interview Questions in R

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Essayez cet exercice en complétant cet exemple de code.

# Compute the average of Hwt
___(cats$Hwt)

# Compute the median of Hwt
___(___)

Modifier et exécuter le code

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Practicing Statistics Interview Questions in R

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Exercise 1: Descriptive statistics Exercise 2: Centrality measures

Exercice en cours

Exercise 3: Variability measures Exercise 4: Categorical data Exercise 5: Survey analysis Exercise 6: Data encoding Exercise 7: Time series Exercise 8: Time series object Exercise 9: Wrangling time series Exercise 10: Principal Component Analysis Exercise 11: PCA - rotation Exercise 12: PCA - dimension reduction

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