Data Science with Python Certification Statistical Analysis and Hypothesis Testing 1

Question 1

What does a p-value less than 0.05 typically indicate in hypothesis testing?

Accepted Answer

There is strong evidence to reject the null hypothesis

Answer

A p-value below 0.05 indicates strong evidence against the null hypothesis, so it is rejected.

Question 2

Which Python library provides the `ttest_ind()` function for an independent samples t-test?

Accepted Answer

scipy.stats

Answer

`scipy.stats.ttest_ind()` performs an independent samples t-test comparing means of two groups.

Question 3

What is the primary purpose of a chi-square test in data science?

Accepted Answer

Testing the relationship between categorical variables

Answer

A chi-square test assesses whether there is a statistically significant association between two categorical variables.

Question 4

Which measure of central tendency is most resistant to outliers?

Accepted Answer

Median

Answer

The median is resistant to outliers because it is based on rank position rather than the actual values of extremes.

Question 5

What does `scipy.stats.shapiro()` test for?

Accepted Answer

Normality of a distribution

Answer

The Shapiro-Wilk test checks whether a sample comes from a normally distributed population.

Data Science with Python Certification Practice Test