Evalguide -

The absolute frequency shows how often certain responses occur. The relative frequency (percentage distribution) means the percentage of individual responses in relation to the whole data set. The frequency distribution can be presented in a table or in a diagram (e.g. in a histogram).

Analysis example for Fragebogen zu Systemarchitektur und Wirkungsgrad [Questionnaire on system architecture and degree of efficiency] (doc, 36 kB, in German) (see page on Questionnaire on system architecture)

The Excel diagram shows how many projects have their core goals in which domains and how many are active in different areas even though these are not within their responsibility: Frequencies degree of efficiency x system architecture (pdf, 19 kB, in German).

Statistical parameters

Different statistical parameters can be calculated in order to obtain information about special characteristics of the attribute distribution:

Measures of central tendency: Which value best represents the distribution?

Arithmetic mean: the sum of all the scores divided by the number of scores (only for interval or ratio-scaled data!). It is also used to calculate a scale value (an average score calculated over all participants and all questions belonging to a scale).

Analysis example for a comparison of project activities with the weighting of program goals

The number of projects that have a certain program goal is compared with the weightings of the program goals (arithmetic mean): Projektaktivitäten und Zielgewichte [Project activities and goal weights] (pdf, 48 kB, in German).

(The number of projects was collected by an interview on project goals and measures; the weighting data was collected using the Gewichtungs-Fragebogen [weighting questionnaire] (doc, 64 kB, in German) (see page on Goal hierarchies).

Mode: the most fre quently occurring score.

Median: divides the distribution into two halves with 50% of the scores above it and 50% of the scores below it.

Scatter: How different are the scores within a distribution?

Variance: The sum of the squared deviations of scores about the mean, divided by the number of scores. Only for interval or ratio-scaled data!

Standard deviation: The square root of variance. Only for interval and ratio-scaled data!

Range of variation: Difference between the smallest and the largest score.

Percentile: Difference between the value that falls above the x % of the scores and that which falls below the x % of the scores.