DA Statistical Analysis 3

Question 1

What is the purpose of ANOVA (Analysis of Variance)?

Accepted Answer

Compare means across three or more groups

Answer

ANOVA tests whether the means of three or more independent groups are statistically different from one another.

Question 2

A positively skewed distribution has its tail pointing in which direction?

Accepted Answer

Right

Answer

In a positively (right) skewed distribution, the tail extends to the right and the mean is typically greater than the median.

Question 3

What is a confidence interval?

Accepted Answer

A range of values likely to contain the true population parameter

Answer

A confidence interval provides a range within which the true population parameter is expected to fall with a specified level of confidence.

Question 4

Which sampling method gives every member of the population an equal chance of selection?

Accepted Answer

Simple random sampling

Answer

Simple random sampling assigns each population member an equal probability of being chosen, eliminating selection bias.

Question 5

What does the Central Limit Theorem state?

Accepted Answer

The sample mean approaches a normal distribution as sample size increases

Answer

The Central Limit Theorem states that the sampling distribution of the mean approaches normality as sample size grows, regardless of the population's shape.

DA - Data Analyst Practice Test

DA - Data Analyst Practice Test

DA Statistical Analysis 3