Chapter #4 - 09/20/24 Flashcards
how to get a good sample
what is a synonym for “good sample” ?
representative study
what are dome examples of research studies ?
- sample surveys
- randomized experiments
- observational studies
what do we mean by a “properly chosen sample” ?
refers to a subset of a population that is selected in a way that accurately represents the larger group
why is a properly chosen sample important ?
this is important in research and statistics to ensure that conclusions drawn from the sample are valid for the entire population
what are some characteristics that makes a chosen sample good ?
- Be Representative
- Avoid Bias
- Be Random
- Be Large Enough
what do we mean by “be representative” ?
It should reflect the characteristics of the whole population (e.g., in terms of age, gender, income, etc.).
what do we mean by “avoid bias” ?
The selection process should not favor certain outcomes or groups within the population.
what do we mean by “be random” ?
Each member of the population should have an equal chance of being selected, reducing the likelihood of selection bias.
what do we mean by “be large enough” ?
The sample size should be sufficient to provide reliable results, considering the variability within the population
how do we preform a sample survey ?
a subgroup sample of a larger population is questioned on a set of topics, and responds what applies best to them
do sample surveys contain intervention or manipulation ?
no intervention or manipulatiiion of the respondents, simply asked to answer some questions
what do randomized experiments do ?
they measure the effect of manipulating the environment in some way
describe a “randomized experiment” :
manipulation is assigned to participants on a RANDOM basis
describe a “explanatory variable” :
the feature that would explain the response (in experiments this is the deature being manipulated)
define “response variable” :
outcome of intrest
what does randomization help with ?
randomization helps to make the groups approximately equal in all respects except for the explanatory variable
EXAMPLE QUESTION :
a trainer wants to investigate how the amount of exercise done by a person affects their resting heart rate. the resting heart rates of people who exercise different amounts are measured and compared
what is the respose variable ?
resting heart rate
EXAMPLE QUESTION :
a trainer wants to investigate how the amount of exercise done by a person affects their resting heart rate. the resting heart rates of people who exercise different amounts are measured and compared
what is the explanatory variable ?
amount of exercise
TRUE OR FALSE
the response variable is CHANGING DUE TO the explanatory variable
TRUE
when comparing response and explanatory variables to independent and dependent variables… which is which ?
independent = explanatory
dependent = response