Stats Chapters 1 -3 Review

Front

What is the mean in a distribution?

Back

The mean is the average of all data points in a distribution, calculated by summing all values and dividing by the number of values.

Front

What is the median in a distribution?

Back

The median is the middle value in a data set when the values are arranged in ascending order. If there is an even number of observations, the median is the average of the two middle values.

Front

How does skewness affect the relationship between mean and median?

Back

In a positively skewed distribution, the mean is greater than the median. In a negatively skewed distribution, the median is greater than the mean.

Front

What is a regression line?

Back

A regression line is a statistical tool used to predict the value of a dependent variable based on the value of an independent variable.

Front

How do you interpret the slope of a regression line?

Back

The slope indicates the change in the dependent variable for each one-unit change in the independent variable.

Front

What does a strong positive correlation indicate?

Back

A strong positive correlation indicates that as one variable increases, the other variable also tends to increase.

Front

What is a z-score?

Back

A z-score measures how many standard deviations a data point is from the mean of the data set.

Front

How do you calculate a z-score?

Back

Z-score = (X - μ) / σ, where X is the value, μ is the mean, and σ is the standard deviation.

Front

What does it mean if a data set is normally distributed?

Back

A normally distributed data set has a symmetric bell-shaped curve, where most of the observations cluster around the central peak.

Front

What is the least-squares method?

Back

The least-squares method is a statistical technique used to determine the best-fitting line by minimizing the sum of the squares of the vertical distances of the points from the line.