Stats 503 Exam 1 Questions and
Answers
Monotonic transformation - Answer-maintains the rank order of the transformed variable
Data generating process - Answer-the set of physical and biological operations that lead
to the observed patterns in the sample data
Exponential distribution - Answer-describes the amount of time that passes before some
event, assuming that the event happens at a constant average rate
Simple random sample - Answer-each sample unit has an equal chance of appearing in
the sample
confidence interval - Answer-a pair of values that have a specified chance of containing
the true value
formal hypothesis test - Answer-evaluates the probability that our data would occur if a
set of assumptions about the population are true
biological model - Answer-describes physical and casual relationships that exist
between different parts of a living system, explains how we think the system works,
makes specific testable predictions
statistical model - Answer-an equation or set of equations that:
- describes the distribution of a variable in a population
- describes functional relationships among variables
- allows valid inferences despite sampling error
parametric model - Answer-assumes that the distribution of a variable in the population
follows a specific functional form
nonparametric method - Answer-do not assume that the distribution of a variable in the
population follows any particular functional form
data - Answer-pieces of information that were collected in a consistent, predefined way,
usually to answer a specific question
multivariate dataset - Answer-includes data on >3 variables for each sample unit
wide-format dataset - Answer-repeated observations of the same individual appear in
multiple columns
, long-format dataset - Answer-have only one column for each variable
bias - Answer-a systematic misrepresentation of the population, so that on average over
many samples, parameter estimates are too high or too low
Likelihood - Answer-measures the probability that the model with the given parameters
would generate the observed data
Fit a model - Answer-set the model's parameters to values that maximize the probability
that the model would generate our data
Likelihood function - Answer-likelihood of generating a given dataset changes as a
function of the parameter value
Maximum likelihood estimate - Answer-the value of parameter that maximizes the
probability of getting the observed data from a given model
variation - Answer-an inherent component
of all living systems
system - Answer-Anything composed of multiple interacting parts
sampling error - Answer-the variation in results from multiple replications of the same
study, due to random chance
census - Answer-collect data on every individual that exists
model - Answer-simplified representation of some part of the real world
inference - Answer-a generalization that you can make about a large group based on
logic and evidence (data) collected on a few members of the group
statistical inference - Answer-a set of formal mathematical procedures used to make
valid generalizations
study population - Answer-the collection of all individual units that we want to draw
conclusions about
sample - Answer-a smaller group selected from the population, that we actually observe
and collect data on
sample units - Answer-the members of the population
statistical sample - Answer-a group of specimens collected from the same study
population
Answers
Monotonic transformation - Answer-maintains the rank order of the transformed variable
Data generating process - Answer-the set of physical and biological operations that lead
to the observed patterns in the sample data
Exponential distribution - Answer-describes the amount of time that passes before some
event, assuming that the event happens at a constant average rate
Simple random sample - Answer-each sample unit has an equal chance of appearing in
the sample
confidence interval - Answer-a pair of values that have a specified chance of containing
the true value
formal hypothesis test - Answer-evaluates the probability that our data would occur if a
set of assumptions about the population are true
biological model - Answer-describes physical and casual relationships that exist
between different parts of a living system, explains how we think the system works,
makes specific testable predictions
statistical model - Answer-an equation or set of equations that:
- describes the distribution of a variable in a population
- describes functional relationships among variables
- allows valid inferences despite sampling error
parametric model - Answer-assumes that the distribution of a variable in the population
follows a specific functional form
nonparametric method - Answer-do not assume that the distribution of a variable in the
population follows any particular functional form
data - Answer-pieces of information that were collected in a consistent, predefined way,
usually to answer a specific question
multivariate dataset - Answer-includes data on >3 variables for each sample unit
wide-format dataset - Answer-repeated observations of the same individual appear in
multiple columns
, long-format dataset - Answer-have only one column for each variable
bias - Answer-a systematic misrepresentation of the population, so that on average over
many samples, parameter estimates are too high or too low
Likelihood - Answer-measures the probability that the model with the given parameters
would generate the observed data
Fit a model - Answer-set the model's parameters to values that maximize the probability
that the model would generate our data
Likelihood function - Answer-likelihood of generating a given dataset changes as a
function of the parameter value
Maximum likelihood estimate - Answer-the value of parameter that maximizes the
probability of getting the observed data from a given model
variation - Answer-an inherent component
of all living systems
system - Answer-Anything composed of multiple interacting parts
sampling error - Answer-the variation in results from multiple replications of the same
study, due to random chance
census - Answer-collect data on every individual that exists
model - Answer-simplified representation of some part of the real world
inference - Answer-a generalization that you can make about a large group based on
logic and evidence (data) collected on a few members of the group
statistical inference - Answer-a set of formal mathematical procedures used to make
valid generalizations
study population - Answer-the collection of all individual units that we want to draw
conclusions about
sample - Answer-a smaller group selected from the population, that we actually observe
and collect data on
sample units - Answer-the members of the population
statistical sample - Answer-a group of specimens collected from the same study
population
