2VL Measurement scales and summarizing data: measures of central tendency Flashcards
What is SME
small- and medium sized enterprise
Name different levels of measurement
nominal, ordinal interval, ratio
Name characteristics of interval level
- number
- can be ordered
- fixed unit of measurement
- 0 does not mean absence of the variable
- 0 has no meaning (0C temperature)
Name characteristics of nominal level
-category
-cannot be ordered
Name characteristics of ratio level
- number
- can be ordered
- 0 is meaningful
- 0 means absence of variable (0 cm hight)
Name characteristics of ordinal level
- tank (no number)
- can be ordered
what is difference between interval and ratio levels
On interval level 0 can be a variable, and on ratio level it means its absence (has special different from other numbers meaning)
Name measures of central tendency
- (arithmetical) mean = average
- median
- mode or modal value
What is the difference between ordinal and nominal?
ordinal can be ordere, nominal cannot
formula of mean
check notes 2VL (add up all the values and divide be the number of values)
what does sigma x in mean formula stand for
sum up all values of variable x
what does N in mean formula stand for
number of observations/ number of values is the variable
alternative formula of mean
check notes 2VL
what is the disadvantage of mean?
extreme values can distort the mean
what is median?
central value of a set of data
