Ch. 1 Introduction & 1.1 NOTES

Statistics Notes

Ch. 1 Introduction & 1.1 NOTES Data Analysis, Making Sense of Data, & Analyzing Categorical Data -I can identify the individuals and variables in a set of data. -I can classify variables as categorical or quantitative​.

Individuals and Variables ● ● ● ●

Example from Book (p. 3-4): Census at School a) b)

Skip c) Analyzing Categorical Data -I can display categorical data with a bar graph and decide if it would be appropriate to make a pie chart. -I can identify what makes some graphs of categorical data deceptive. Describing Categorical Data:

Types of Displays: ● Bar Graphs ○ Most often used _________________________________________________________ ○ Often easier to __________________________________________ ○ Can display ______________________ or ___________________________ ● Pie Charts ○ Only used to compare a category’s ______________________ ○ _______________________ relative frequency

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Statistics Notes Deceptive Graphs

Source: https://gator.gatewayk12.org/~smcgrail/myweb/po werpoint/misleading_graphs/here_are_some_exa mples_of_mislea.htm

-I can calculate and display the marginal distribution of a categorical variable form a two-way table. -I can calculate and display the conditional distribution of a categorical variable for a particular value. of the other categorical variable in a two-way table. -I can describe the association between two categorical variables by comparing appropriate conditional distributions.

Two-Way Table Displays the relationship between TWO categorical variables. TITANIC PASSENGERS

  First Alive 203

Second Third 118 178

Crew 212

Total 711

Dead 122 Total 325

167 285

673 885

1490 2201

528 706

What percent of first class passengers died?

What percent of third class passengers died?

What percent of the total passengers died?

What percent of the survivors were in the 1st class?

Here is a suggestion made by historians:​ ​First-class passengers received special treatment in boarding the lifeboats, while some other passengers were prevented from doing so (especially third-class passengers).

Is there any truth to this? Use the data to support your answer.

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Statistics Notes

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