One-Variable Stats
Name the measure of center that is resistant to outliers.
What is the median?
List the five numbers in a five-number summary.
What is the min, quartile 1, median, quartile 3, and max?
True or False: A histogram shows individual Data values?
What is False?
What percentage of data falls within 1 standard deviation of the mean in a normal distribution?
What is ~68%?
Name two common types of plots used for one-variable data besides a histogram
What is a dotplot, stem-and-leaf, boxplot, etc.
What does the standard deviation describe?
What is how spread out the data are from the mean?
Which numbers determine the IQR?
What is Q3-Q1?
What is the difference between a histogram and a bar-chart?
Where would the mean and median fall in a perfectly normal curve?
What is they're the same value?
When you see a ga or cluster in a histogram, it might indicate that...
A set of data has mean 50, median 70. Is it skewed left or right?
What is skewed left?
If Q1=10 and Q3=30, find the IQR.
What is 20?
What shape histogram suggests a normal distribution?
What is symmetric and bell-shaped?
z=+2 means the data point is how far from the mean?
What is two standard deviations above the mean?
An observation lies far outside the rest of the data. What's it called and how might it affect the mean?
What is an outlier? It pulls the mean toward it.
Explain how to calculate a z-score.
What is (the value minus the mean) divided by the standard deviation?
Using the 1.5xIQR rule, what are the upper/lower fences for Q1=5, Q3=20?
What is -17.5 and 42.5?
Which bin width would reveal more detail: 1 or 10?
What is 1?
About what percentage of data lies above +-3Sx in a normal distribution?
What is ~0.3%?
Looking at a boxplot, how can you tell if a distribution is skewed?
Give an example where the mean is a poor measure of center.
What is skewed data with outliers?
What is one advantage of a boxplot over a histogram?
Why might two histograms with the same data look different?
What are different bin widths or starting points?
How would you check if data are approximately normal?
What is check the histogram shape and compare to the empirical rule percentages?
You're shown a histogram with a longer tail leading toward the lower values in the data set. What does this indicate?
What is left-skewed Data?