Chapter 13 Levels of Measurement & Quantitative Analysis Flashcards
Purpose of Statistical Analysis
To describe the data (sample characteristics)
To test hypotheses
To provide evidence regarding the measurement properties of quantified variables
Levels of Measurement
Nominal, ordinal, interval, ratio
Nominal
Lowest level
Involves using #s simply to categorize attributes
Ordinal
Ranks people on an attribute
Interval
Most common data nurses use
Ranks people on an attribute & specifies the distance between them
Ex) Temp, salary
Ratio
Highest Level
Ratio scales, unlike interval scales, have a meaningful zero and provide information about the absolute magnitude of the attribute
Descriptive Statistics
Concerned w/ describing the target population
Organize, analyze, & present the data in a meaningful manner
Final results are shown in form of charts, tables, & graphs
Describes the data which is already known
Measures of central tendency (mean/median/mode)
Spread of data (range, SD- standard deviation)
Inferential Statistics
Make inferences from the sample & generalize them to the population
Compares, tests, & predicts future outcomes
Final results is probability scores
Tries to make conclusions about the population that is beyond the data available
Hypothesis tests, Analysis of variance, etc
Frequency Distributions
A systematic arrangement of numeric values
on a variable from lowest to highest and a count of the number of times (and/or percentage) each value was obtained
Frequency Distributions: Descriptions & Presentations
Frequency distributions can be described in
terms of:
* Shape
* Central tendency
* Variability
Can be presented in a table (Ns and
percentages) or graphically (e.g., frequency
polygons)
Many nurses interpret data as if they were:
A) Nominal data
B) Interval data
C) Ratio data
D) Operational data
B) Interval data
