Download ap statistics midterm review sheet

AP STATISTICS MIDTERM REVIEW SHEET
Following are some of the key topics covered in the first half of our AP Statistics course.
Use this sheet as a study guide for the midterm—there will be questions on all of these
topics.
Measures of Center and measures of dispersion

Mean, Median, Mode

Range, Standard Deviation

Be able to compute and compare mean and median of a set of data

What happens to mean, median, and standard deviation when you manipulate
the data?
o Example: What happens to the mean, median, and standard deviation
when you increase all data values by 100; double all data values; increase
all data values by 25% (be careful…increasing by a percent is actually like
multiplication)?

What is an outlier? Influential point?

Be able to construct a box plot given a set of data
o 5 number summary – min, Q1, median, Q3, max

What happens to the relationship between mean and median when the data is
skewed?
o Example: When symmetrical (like in the normal distribution), mean and
median are equal—what happens to the relationship when the data is
skewed left? Skewed right?
Random number table

Know how to use the random number table
o You will be given an excerpt from the random number table—know how to
apply it.
Sampling and Surveys

Simple random sample, convenience sample, cluster sample, voluntary response
sample

Census

Sampling Bias
o Voluntary Response, Response, Non-Response, etc.

Which plot in good for categorical data? Which plot is not good for categorical
data?
Normal Distribution

Be able to calculate z-scores for normally distributed data and use those zscores to find normal probabilities.

What does a z-score actually represent?
o For example, a z-score of 2 means that the data value is 2 standard
deviations above the mean.
o A z-score of -2.6 means that the data value is 2.6 standard deviations
below the mean.
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Linear Regression

Interpret the y-intercept of a least squares regression line
o The y-intercept is your y-value when x is zero.

Interpret the slope of a least squares regression line
o Remember to interpret slope you see what happens to the y if you
increase x by 1 (as x increases by 1, y changes by __________)…then
put it in context of the question.
 Example (hypothetical): The slope of a regression line relating
income (y) to years attended college (x) is 3000. Interpreting this
slope you would say ‘Income increases by $3000 for each
additional year attended in college’.

Be able to compute the equation of a least-squares line using the formulas on
your AP Stats formula sheet:
b1  r
o




sy
sx
b0  y  b1 x
yˆ  b0  b1 x
You will be given the information you need—you just need to plug the given
information into the formulas above (in the order above). We will review this
further in class…
Interpret r and R2 (remember, if given R2 only, r can be positive or negative…r
will have the same sign as the slope.)
Create a scatterplot of bivariate data using the graphing calculator.
Be able to write the equation of a least-squares line when given a computer
printout (‘Coef’ column)—‘Constant’ is the y-intercept (b0) and the number below
it is the slope (b1).
Probability

Expected value

Understand and apply the Addition Rule, the Multiplication Rule, and Conditional
Probability formula.

Know how to do a ‘tree-diagram problem’…Chapter 15.

Normal Distribution—as stated above, you should be able to calculate normal
probabilities using either the z-chart in the appendix or by using the normalcdf
and invNorm functions in the graphing calculator.

Determine compound and conditional probabilities by reading a table of data.
Just like the in-class Chapter 15—Conditional Probability handout (it is on
Teacherweb).
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