Stats chapter 2 notes - Marianna Johnson PDF

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Marianna Johnson...

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Chapter 2: Organizing & Visualizing Variables 1. Datasets- contains information regarding the customer’s credit card limit, demographic information, and the amount they owe 2. Categorical data is grouped into some sort of category, examples are, Gender, Mobile carrier, The state that a person lives 3. Summary table- presents the statistical information about data in table form and it tallies the frequencies or percentage of items in a set of categories so you can see the differences 4. Contingency tables- (also called crosstabs or two-way tables), they are used to summarize the relationship between categorical variables 5. Bar chart or bar graph- represents data with rectangular bars with heights or lengths proportional to the values that they represent, can be plotted vertically or horizontally 6. Pie chart or circle chart- circular chart which is divided into slices, arc length is proportional to the quantity 7. Side by Side chart- compare and contrast multiple categories at the same time 8. Ordered array- sequence of data, smallest to largest, shows range Frequency Distribution 1. How often something occurs is frequency 2. Frequency Distribution table is used when counting frequencies 3. Frequency- the count of occurrences of values within that particular group or interval Why do we use Frequency Distributions?????? 1. Quick visual interpretation of data 2. Raw data into a more useful form 3. Enables the major characteristics of the data set Histograms 1. A graphical representation of the distribution of numerical data is a histogram 2. No gaps between adjacent bars 3. Vertical axis- and the height of the bars represents the frequency, relative frequency, or percentage Scatter Plots 1. Numerical data consisting paired observations taken from two numerical variables is a scatter plot 2. They are used to examine relationships between two variables...