1. Chapter

Statistic is a tool to help process, summarize, analyze and interpret data

The size of a population (collection of all items)

N is representing the sample of the population N

A parameter is a specific characteristic of a population

Statistic

• choosen by chance

• each n is equally likely chosen

—> randomsample is the result

• descriptive

• inferential (analystisch, folgernd)

• collect data

• present data

• summarize data

• giving predictions based on assumption that were made by a sample

—> Hypothesis testing

• Categorial (Defined Categories e.g. colour of eyes)

• Numerical

  • discrete (counted items e.g. Number of children)

  • Continous (weight)

1. Ration Data

2. Interval Data

3. Ordinal Data

4. Nominal Data

• list or table

• class groupings

• corresponding frequencies

• it somehow summarize data

• it condenses the data

• quick visual interpretation

5-20

• create a distribution that is not to jagged or to blocky

• trial and error

• show the pattern (Verhalten/ Muster) of the data

• display essential information

• Cummunicate clearly and accurately

• avoid distortion (verzerrung)

• They indicates the position of a value relative the the entire set of data

  
  

• ignores how data is distributed

• sensitivity to outliers

• each value is used in the data set

• values far from the mean are giving extra weight