Statistics

1.1 -

1.2 -

1.3 -


Chapter 2 - Tables and graphs

2.1 - Frequency Tables

  • organizes and summarize data

  • data in categories with numbers of data value in each category


Definitions -

lower class limits: smallest number that can belong in the categories

upper class limits: largest number that can belong in the categories

class width: how many numbers between each cat.

midpoints - median of each cat

class boundry - (upper limit + lower limit of the next cat) / 2 then difference between this and class width


convienience number - (max value) - (minimum values) / number of classes

relative frequency table is in %


2.2 - histogram

easy to interpret

  • visual representation

  • bar graph basically

  • shapes, distribution, center, spreads, outliers


anaylizing - CVDOT

center of sata, variation, shape of distribution, outliers, time

socv?


bell shaped = normal distribution

skewness - right is positive (lower)

- left is negatively (higher)


is not a normal distribution if points not straight line / systematic pattern for quantile plots


2.3 - graphs, enlighten/deceive

  • dotplots, each data is a dot above horizontal scale (individual data)

  • stemplot, values are separted 2 l 22233344666778

  • histograms


Chapter 3 - Describing, exploring, and comparing data


3.1 - Measures of center → VVV

obtain a value that is the center of a data set, along ith mean and median

  • mean (adding all data values thhen dividing by # of values)

    • not resistant to outliers (resistant if outliers don’t affect it much)

    • varies less


  • notion

E thing - sum of the data values

x - variable to represent indivisual data values

n - # of data values in a sample

N - # of data values in a population

x bar - mean of a set of sample values