1. Distributions and Graphical Representations

2. Statistics
the science of collecting, analyzing, and drawing conclusions from data

3. Descriptive statistics
the methods of organizing & summarizing data

4. Inferential statistics
involves making generalizations from a sample to a population

5. Population
The entire collection of individuals or objects about which information is desired

6. Sample
A subset of the population, selected for study in some prescribed manner

7. Variable
any characteristic whose value may change from one individual to another

8. Data
observations on single variable or simultaneously on two or more variables

9. Types of Variables

10. Categorical variables
or qualitative
identifies basic differentiating characteristics of the population

11. Numerical variables or quantitative
observations or measurements take on numerical values
makes sense to average these values
two types - discrete & continuous

12. Discrete (numerical)
listable set of values
usually counts of items

13. Continuous (numerical)
data can take on any values in the domain of the variable
usually measurements of something

14. Classification by the number of variables
Univariate - data that describes a single characteristic of the population
Bivariate - data that describes two characteristics of the population
Multivariate - data that describes more than two characteristics (beyond the scope of this course

15. Identify the following:
gender
age
hair color
smoker
systolic blood pressure
number of girls in class
categorical
numerical

16. Types of Distributions
4 common types

17. Symmetrical
refers to data in which both sides are (more or less) the same when the graph is folded vertically down the middle
bell-shaped is a special type
has a center mound with two sloping tails

18. Uniform
refers to data in which every class has equal or approximately equal frequency

19. Skewed (left or right)
refers to data in which one side (tail) is longer than the other side
the direction of skewness is on the side of the longer tail

20. Bimodal (multi-modal)
refers to data in which two (or more) classes have the largest frequency & are separated by at least one other class

21. Dotplots Stem & leaf plots Histograms Boxplots
How to describe a graph
Dotplots
Stem & leaf plots
Histograms
Boxplots
Do after Features of Distributions Activity

22. 1. Shape - Type of distribution
refers to the overall shape of the distribution
symmetrical, uniform, skewed, or bimodal

23. 2. Center discuss where the middle of the data falls
three types of central tendency
mean, median, & mode

24. 3. Spread discuss how spread out the data is
refers to the variability of the data
Range, standard deviation, IQR

25. 4. Unusual occurrences
outliers - value that lies away from the rest of the data
gaps
clusters
anything else unusual

26. 5. In context
You must write your answer in reference to the specifics in the problem, using correct statistical vocabulary and using complete sentences!