Unit 1 Flashcards
What is the goal of statistics?
To understand sample data and use it to make conclusions about aspects of a population.
Observational Units:
Individual things on which data is recorded
Variables:
The characteristics of the observational units being recorded
Data:
The recorded results of a study
Variables:
The characteristics of the observational units being recorded
1) Quantitative: result is a set of numbers
2) Categorical: result is a set of categories
Population:
The entire collection that we want to learn about “All”
Sample:
The portion of the population used to gain information about the population and is composed of observational units
Parameter:
Numerical characteristic of a population that is typically unknown.
The study is conducted to understand something about the parameter.
Either Pi- categorical or Mu- quantitative
Statistic:
Numerical characteristic of observed sample that is calculated from the sample data and is therefore known.
Either P-hat: categorical or X-bar: Quantitative
Pi:
Parameter of categorical variable. Proportion of observational units belonging to particular category.
P-hat:
Statistic of categorical variable. Proportion of observational units belonging to success category value calculated from observed data
Mu:
Parameter with quantitative variable. Mean values of variables for the entire population–typically unknown
X-Bar:
Statistic with quantitative variable. Mean of values of variable from sample calculated from observed data
N:
Sample size, number of observational units in the sample
Probability of an event:
Proportion of times event occurs in the long run of trial under identical conditions
