What is statistics? Flashcards
what is statistics?
- brand of mathematics that deals with: = data collection = summary = analysis = interpretation provides a bridge between the real world and the mathematical models that attempt to explain it, proving a metholdoy to assess discrepancies between reality and theoretical models
what is data?
raw form, doesn’t tell you anything without being manipulated in some way
what is informatio?
covered data, used by human reader
what is knowledge?
information that converted when users understood and internalises the info
what are the types of data?
- numeric
- text
- visual
could be national level firm level product level individual level
what does population mean?
complete set of individuals, objects or scores of interest
e.g. studying an phenonomn in a population
what is the problem with studying the population?
for complete knowledge you have to study every indidivudal
- too large
- costs (time and money)
what is a sample?
subset of population, sample may be classed as random or convinence
they are representative fo the population
what is sample size?
number of individuals of the sample
population study conducted on samples drawn from it
what are the types of reasoning?
deductive
inductive
extrapolttion
what is deductive reaosning?
from general to particular
if premises are true in entire pool.ualtion then it garuntees they will be true for sample
what is inductive reasoning?
does not garuntee certainty of concussions, may be true for population, but it is the only way to generate new knowledge
what is extrapolation reasoning?
estimating/conculding by assuming that existing trends will continue ]
use specific details to make general conclusion
predict future outcomes based on known facts
what is the deductive process?
deduction theory hypotheses observation confirmation
what is the inductive process?
induction observation pattern hypotheses theory
what is sampling?
process of selecting elements elements included in a sample
what is sampling frame?
how you can get access
what is theoretical sampling?
who do you want to generalise the study to
what are the types of sampling?
- random
- non random
- convienve
what is random sampling?
indidivuduals randomly selected, same liklihood of being selected (equi probility)
done with replacement, each selection is independent of others
what is non random sampling?
sample not random, some have higher chance of being picked than others
what is convenience smapling/
people who are easy to reach or contact e.g. nearest people to you
what is a variable?
symbol that can take on any specified set of values
characteirics of an item measured
what are values?
results of measuring
what are the two levels of measurement?
qualaititave
quantitative
what are qualitative levels of measurement?
- nominal
- dichotomous
- ordinal
what are quantitative levels of measurement?
- ratio
- interval
what is nominal level of measurement?
qual - no intrinsic order where numbers have no value - numbers used as tags - how are you feeling 1 = good 2 = bad - categories
what is dichotomous measurement?
only two categories
yes / no
what is ordinal measurement?
- ranking or ordering
- without establishing the degree of variation between them
what is ratio measurement?
has a meaningful zero
interval data
what is interval data?
measured along a continuum
80-70 same as 40-30
the interval can be interpreted
no absolute zero
what is dependant variable?
variable of primary interest not controlled by experiment (response)
what is the independent variable?
manipulated in an experiment (predicto)
what is a data table?
each column is a variable
each row is an indidivudal
what is the statistical cycle/
cycle of events
- research design
- sampling
- descriptive stats
- inferential stats
- prediction
what is research design?
study begins with a previous design in whichh study goals population, variable and sample size are met
what are descriptive stats?
describing and summarising the info of the sample
what are inferential stats?
info obtained is projected on a mathematical model that intends to explain what happened ni population and the model is validated
how is a prediction done?
validated model form infereteial statistics is used to make predictions and draw conclusions
