Chapter 1 Flashcards
what are the 2 branches of statistics?
descriptive statistics and inferential statistics
descriptive statistics
organize, summarize, and communicate numerical information (ex: the average shark is 15 feet long)
inferential statistics
use sample data to make estimates about the larger population
population
a collection of all possible members of a defined group
sample
a set of observations drawn from the population of interest
variable
things we measure, observations that can take on a range of values
discrete observations
can only take on specific values (ex: whole numbers)
continuous observations
can take on a full range of values
what are the measurement scales for variables?
nominal, ordinal, interval, ratio (noir)
nominal scale
most simple; a unique name/label (discrete)
ordinal scale
adds requirement of order/rank; ex: birth order (discrete)
interval scale
adds requirement of equal intervals; ex: temp in F or C (continuous)
ratio scale
adds requirement of a meaningful zero (continuous)
levels
the discrete values or conditions that variables can take on (ex: male is a level of the variable gender, gender could have 3 levels- male/female/fluid)
predictor variable
has at least 2 levels we either manipulate or observe to determine its effects on outcome variables (IV)
outcome variable
the variable we hypothesize to be related to or caused by changes in predictor (DV)
confounding variable
a variable you try to control or randomize away; interferes with conclusions
reliable
measure is consistent
valid
measures what it is intended to measure
operational definition
specifies the operations or procedures used to measure or manipulate a variable
experiment
studies in which participants are randomly assigned to a condition or level of one or more IVs
between-groups design
an experiment where different people complete the tasks and comparisons are made between the groups
within-groups design
same participants do things more than once and comparisons are made over time
correlational studies
don’t manipulate either variable, variables are assessed as they exist
quasi-experiment
active manipulation of IV, typically not random assignment
data ethics
a set of principles related to all stages of working with data
open science
approach to research that encourages collaboration, sharing of research methodology, data, and statistical analyses
HARKing
Hypothesizing After Results are Known
