chapter 2 Flashcards
primary and secondary data
primary data:
data collected through firsthand research for an intended purpose
Secondary data:
data obtained second hand through research conducted by another person for another purpose
qualitative data and quantitive data
Qualitative data:
data that describes characteristics and qualities
Quantitative data:
data that includes measurable values and quantities and can be compared on a numerical scale
Percentage change
a calculation of the degree of change in a value over time
measures of central tendancy, mean, median and mode
Measures of central tendency:
-a category of statistics that describes the central value of a set of data
Mean:
a statistic that is the average value of a set of data
median:
the middle value in an ordered set of data
mode:
the value that occurs most frequently within a set of data
measure of variability
Measures of variability:
a category of statistics that describe the distribution of data
Standard deviation:
a statistic that shows the spread of the data around the mean
tables
Tables are a way of organising data and/or summary statistics to clearly compare the results of different groups in a study.
-If data cannot be presented in one or two sentences, then a table should be used instead of explaining the data in the text of a report.
analysing the quality of data:
true value
the value, or range of values, that would be found if the quantity could be measured perfectly
analysing the quality of data:
accuracy
how close a measurement is to the true value of the quantity being measured
analysing the quality of data:
precision
how close a set of measurement values are to each other
analysing the quality of data:
repeatability
the closeness of the agreement between successive measurements of the same quantity, carried out under the same conditions
analysing the quality of data:
reproducibility
the closeness of the agreement between measurements of the same quantity, carried out under different conditions
analysing the quality of data:
replicability
giving the same answer to a scientific question when a different method is used and different data is obtained
analysing the quality of data:
validity
whether a measurement measures what
it is supposed to measure
analysing the quality of data:
internal validity
whether a study investigates what it sets out or claims to investigate
analysing the quality of data:
external validity
whether the results of research can be applied to similar individuals in a different setting