Section 1.1 Part 1 AP Statistics CASA CASA, AP Stats 05-06, Section 1.1.1

We study statistics because… … anecdotal evidence is not reliable. … we don’t wish to be lied to. … spotting trends helps us make good decisions Simply, we study statistics because we want to make sense of the world. CASA, AP Stats 05-06, Section 1.1.1

Vocabulary Individuals – objects in a data set. Sometimes referred to as x1, x2, x3, etc. Variable – any characteristic of an individual Thinking of the individuals in this room, what might some of their characteristics? CASA, AP Stats 05-06, Section 1.1.1

Categorical vs. Quantitative Categorical variables places individuals in one of several groups. Quantitative variable takes numerical values for which arithmetic operations like adding make sense. Of the variables describing the members of the class, which are categorical and which are quantitative? CASA, AP Stats 05-06, Section 1.1.1

Distribution “The distribution of a variable tells us what values the variable takes and how often it takes these values.” How distributions differ between categorical and quantitative variables? CASA, AP Stats 05-06, Section 1.1.1

Bar and Pie Charts Both show relative frequencies of categorical values in a data set. CASA, AP Stats 05-06, Section 1.1.1

Problems with Pie Charts CASA, AP Stats 05-06, Section 1.1.1

Attributes of a “good” chart Title Axis Labels Consistent Scale CASA, AP Stats 05-06, Section 1.1.1

Assignment Exercises 1.1 – 1.6, Practice of Statistics CASA, AP Stats 05-06, Section 1.1.1