Statistical Concepts and Inference Flashcards
7 cards from real Data Science practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Statistical Concepts and Inference flashcards as text
In Bayesian inference, the posterior distribution is proportional to:
Answer: The likelihood times the prior
Bayes' theorem states the posterior is proportional to the likelihood multiplied by the prior.
A prior distribution in Bayesian analysis represents:
Answer: Beliefs about a parameter before observing data
The prior encodes existing beliefs or knowledge about a parameter before the current data is seen.
Which test is appropriate for comparing the means of two independent groups with continuous outcomes?
Answer: Independent samples t-test
An independent samples t-test compares the means of two separate groups.
A chi-square test of independence is used to assess:
Answer: Association between two categorical variables
The chi-square test of independence evaluates whether two categorical variables are associated.
When should ANOVA be preferred over multiple t-tests?
Answer: When comparing three or more group means while controlling the family-wise error rate
ANOVA compares three or more means in one test, avoiding the inflated Type I error of many pairwise t-tests.
A small p-value combined with a tiny effect size in a very large sample suggests:
Answer: Statistical significance that may lack practical significance
Large samples can make trivial effects statistically significant, so significance does not guarantee practical importance.
The standard error of the mean decreases as:
Answer: The sample size increases
Standard error equals the standard deviation divided by the square root of n, so it shrinks as n grows.