AP Statistics. Exam Review April 25, 2009 Corey Andreasen (Thanks to Paul L. Myers and Vicki Greenberg of Woodward Academy, Atlanta, GA for the structure of this review). Agenda. Exam Format/Topic Outline Breakdown Burning Questions – I don’t get it! “Challenging” Concepts r and r 2
April 25, 2009
(Thanks to Paul L. Myers and Vicki Greenberg of Woodward Academy, Atlanta, GA for the structure of this review)
Describing patterns and departures from patterns (20%-30%)
Exploring analysis of data makes use of graphical and numerical techniques to study patterns and departures from patterns. Emphasis should be placed on interpreting information from graphical and numerical displays and summaries.
The parents have constructed the two catapults according to slightly different plans. They want to test these catapults before building additional ones. Under identical conditions, the parents launch 40 Ping-Pong balls from each catapult and measure the distance that the ball travels before landing. Distances to the nearest centimeter are graphed in the dotplot below.
A manufacturer of dish detergent believes the height of soapsuds in the dishpan depends on the amount of detergent used. A study of the suds’ height for a new dish detergent was conducted. Seven pans of water were prepared. All pans were of the same size and type and contained the same amount of water. The temperature of the water was the same for each pan. An amount of dish detergent was assigned at random to each pan, and that amount of detergent was added to that pan. Then the water in the dishpan was agitated for a set of amount of time, and the height of the resulting suds were measured.
A plot of the data and the computer printout from fitting a least-squares regression line to the data are shown below.
This graph shows the data transformed into "standard scores" zx and zy. What do you notice about the plots?
This is the plot of calories of different brands of pizza.
What is your best estimate of the number of calories in a pizza?
This is an example of a Free Response question in which the first parts involve Exploratory Data Analysis and later parts involve inference.
Planning and conducting a study (10%-15%)
Data must be collected according to a well-developed plan if valid information on a conjecture is to be obtained. This includes clarifying the question and deciding upon a method of data collection and analysis.
Exploring random phenomena using probability and simulation (20%-30%)
Probability is the tool used for anticipating what the distribution of data should look like under a given model.
All bags entering a research facility are screened. Ninety-seven percent of the bags that contain forbidden material trigger an alarm. Fifteen percent of the bags that do not contain forbidden material also trigger the alarm. If 1 out of every 1,000 bags entering the building contains forbidden material, what is the probability that a bag that triggers the alarm will actually contain forbidden material?
= .001(.97) + .999(.15) = .15082
P(F|A) = .00097/.15082 = 0.006
Estimating population parameters and testing hypotheses (30%-40%)
Statistical inference guides the selection of appropriate models.
Are M&M’s Color Distributions Homogenous?