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

Estimate missing data values

Answer

Measure data skewness

Answer

Calculate confidence intervals

Question 2

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

Accepted Answer

Right

Answer

Left

Answer

Both directions equally

Answer

Toward the mean

Question 3

What is a confidence interval?

Accepted Answer

A range of values likely to contain the true population parameter

Answer

The exact true value of a population parameter

Answer

The p-value expressed as a percentage

Answer

The standard deviation of a sample

Question 4

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

Accepted Answer

Simple random sampling

Answer

Stratified sampling

Answer

Convenience sampling

Answer

Cluster sampling

Question 5

What does the Central Limit Theorem state?

Accepted Answer

The sample mean approaches a normal distribution as sample size increases

Answer

All populations are normally distributed

Answer

Outliers should always be removed

Answer

Variance equals the standard deviation squared

Question 6

What is multicollinearity in regression analysis?

Accepted Answer

When two or more independent variables are highly correlated with each other

Answer

When the dependent variable is categorical

Answer

When residuals are not normally distributed

Answer

When the model has too few predictors