AP Statistics Introduction What is Statistics Statistics is
- Slides: 14
AP Statistics: Introduction
What is Statistics? Statistics is the science (and art) of learning from data. It includes: 1. 2. 3. 4. A Analyzing Data Producing Data Probability Inference statistically literate person will begin his/her examination of a set of data with the following questions:
Who? What individuals (people/animals/things*) are being described by the data? How many individuals are being studied?
What? What variables (characteristics of individuals) are being described by the data? How many variables are there? What kind of variables are being studied? Categorical –places individuals into one of several groups or categories. Quantitative – takes numerical values for which arithmetic operations such as adding and averaging make sense. NOT ALL NUMERICAL DATA IS QUANTITATIVE!!!!!
Why? Why were the data gathered? Beware of BIAS!
How? There are 2 different types of statistical studies…
Distracted Driving Experiment Research from the University of Utah Video: The New York Times Distracted Driving Experiment: Deliberately imposes some treatment on individuals to observe their responses
What is the role of statistics? To pass laws against cell phone use in cars, evidence must be produced which proves cell phones are detrimental to safety It is not enough to infer from convenient observations that it “seems like people on cell phones are more distracted than other drivers”
Tanning Beds and Cancer Research ABC reports on American Cancer Society findings Observational Study: observes individuals and measures variables of interest but does not attempt to influence the response. Also includes surveys
Which type of study is better? An experiment is better because it enables the researcher to control for some of the confounding variables. If we simply observe drivers who get in accidents when they are on their cell phones, what variables might get in the way? Weather, type of road, how many people are in the car, type of car
Why don’t we always do experiments? Tanning study…. can we assign people to use a tanning bed a certain # of times a week? External Validity (the extend to which we can apply our results to the outside world) is also an issue. Milgram Experiment
Gallup Polls Regularly conducts public opinion polls in more than 140 countries Reliable data since survey methods involve random sampling and careful wording of questions www. gallup. com
Population vs. Sample Population: the entire group of individuals that we want information about Sample: the part of the population that we will actually examine in order to gather information Find an interesting Gallup Poll and determine the sample and the population
AP Statistics Data Collection https: //spreadsheets. google. com/viewform? fo rmkey=d. GFxc 3 Rn. Tmp. Ve. XFf. MDRJMlh. RM 0 x. L enc 6 MQ Visit my Web Page to find the link