Basic Statistics with Python

Which measure of central tendency is not affected by outliers?

• Mean

• Median

• Mode

• Range

Answer explanation

The median is the middle value of a dataset when it is ordered, and it is not affected by extremely high or low values (outliers).

What does a histogram represent in data analysis?

• The relationship between two variables

• The distribution of a single variable

• The central tendency of data

• The spread of data around the mean

Answer explanation

A histogram shows the distribution of data points for a single variable, with bars representing the frequency of data points in each bin.

In a histogram, what does the height of each bar represent?

• The mean of the data

• The cumulative frequency of data points

• The median of the data

• The frequency of data points within a bin

Answer explanation

• The height of each bar in a histogram represents the number of data points (frequency) that fall within the range of that bin.

What does the box in a boxplot represent?

• The range of the data

• The min and max of data

• The interquartile range (IQR)

• The mode of the data

Answer explanation

The box in a boxplot represents the IQR, which is the range between the first quartile (Q1) and the third quartile (Q3).

What does a scatter plot with points closely clustered around a line indicate?

• It doesn't have any meaning

• A strong relationship between the variables

• A small spread of data

• An equal distribution of the variables

Answer explanation

When points are closely clustered around a line, it indicates a strong relationship or correlation between the two variables.

How can outliers be identified in a dataset?

• Using a scatter plot

• Using a boxplot

• Using the mean and standard deviation

• All the above

Answer explanation

Outliers can be identified using scatter plots, boxplots, or by calculating the mean and standard deviation to see which values deviate significantly from the rest of the data.

Which method can be used to handle missing data in a dataset?

• Removing rows with missing values

• Imputing missing values with the mean or median

• Using algorithms that support missing values

• All of the above

Answer explanation

Handling missing data can be done by removing rows, imputing missing values with statistical measures like mean or median, or using machine learning algorithms that can handle missing data

Which library is MOST commonly used in Python to make HTTP requests for web data extraction?

• http

• json

• requests

• pandas

Answer explanation

The requests library is widely used in Python for making HTTP requests to access web data as it has a more user-friendly API and more features than urllib.

Which function in pandas is used to generate descriptive statistics of the DataFrame?

• dataframe.info()

• dataframe.describe()

• dataframe.stats()

• dataframe.data()

What does the standard deviation measure in a dataset?

• The distance between the min and max

• The middle value of the dataset

• • The spread of the data around the mean

• The number of data points in the dataset

Answer explanation

The standard deviation is a measure to quantifies how much the values in the dataset differ from the mean (average) of the dataset. A lower standard deviation indicates that the values are closer to the mean, while a higher standard deviation indicates that the values are more spread out.