WGU D196 OA TEST BANK EXAM QUESTIONS AND
CORRECT ANSWERS| ACCURATE REAL EXAM WITH
FREQUENTLY TESTED QUESTIONS AND
RATIONALE|ALREADY A GRADED|GUARANTEED
PASS|LATEST UPDATE 2025.
Coefficient - CORRECT ANSWER A number by which a variable is being multiplied.
Coefficients are written in front of variables. 16x, 16 is coefficient. If there is no number you
assume an invisible1.
Term - CORRECT ANSWER Can be a single constant, a single, or a number of constants and
variables multiplied together.
Algebraic expression - CORRECT ANSWER String of terms connected by division, addition,
and subtraction.
How to write an algebraic expression - CORRECT ANSWER Constants at end. Write terms
with the largest exponents first. Always write in descending order of exponent value with
constants at the end.
Inverse operation - CORRECT ANSWER Operations that undo each other. Subtraction is
inverse of addition. Division is inverse of multiplication.
Like terms - CORRECT ANSWER Have the same variable with the same exponent
Degree of an expression - CORRECT ANSWER Refers to largest exponent in an expression
Linear - CORRECT ANSWER Has degree of 1
Quadratic - CORRECT ANSWER Has degree of 2
Cubic - CORRECT ANSWER Has degree of 3
Constant - CORRECT ANSWER Has degree of 0
Distributive property - CORRECT ANSWER Principle used to multiply a single term by
multiple terms. If there are parenthesis around multiple terms which are in turn multiplied by a
single term, we can use this property.
Histogram - CORRECT ANSWER A graphical representation -- bars, measuring the frequency
within each interval
Skewed right - CORRECT ANSWER Not a symmetric distribution, the tail is on the right
Measures of center - CORRECT ANSWER Median, the mean (and mode)
,Measures of spread - CORRECT ANSWER Range, IQR & standard deviation
Standard Deviation Rule - CORRECT ANSWER 68% of the data are within 1 standard
deviation,
95% are within 2,
99.7% are within 3 standard deviations from the mean.
median (for center) & IQR (for spread) - CORRECT ANSWER skewed data uses these for
center and spread
Scatter plot - CORRECT ANSWER A graphical representation of Q -> Q
Two way table - CORRECT ANSWER A graphical representation of C -> C
Side-by side box - CORRECT ANSWER A graphical representation of C -> Q
Interpolation - CORRECT ANSWER Making predictions *within* the range of your data. This
is usually accurate.
Extrapolation - CORRECT ANSWER Making predictions *outside* of the range of your data.
This is generally a bad idea.
Simpson's Paradox - CORRECT ANSWER When split up, each data set can have a pattern
which goes away when all the data is combined.
Prospective study - CORRECT ANSWER Is a study that's done over time to find results / A
study watching for outcomes during the study period
Unbalanced response - CORRECT ANSWER Giving more options that are negative than
positive options (or vice versa) which biases the responses towards the more common option
Matched pairs - CORRECT ANSWER Grouping two similar subjects and giving different
treatments/procedures to each in order to compare the differences. For example, having one twin
take a medication while the other twin does not.
Population - CORRECT ANSWER The entire group you are trying to describe or understand.
Sampling frame - CORRECT ANSWER List of group from which you choose your sample.
Sample - CORRECT ANSWER The group that is actually picked to be included in a study
Simple random sample - CORRECT ANSWER making a selection by following a random
pattern and selecting without replacement. Unbiased.
,Systematic sample - CORRECT ANSWER Sample is selected by listing the sampling frame,
then making a selection by following a simple pattern (eg. Every 20th name). Unbiased.
Voluntary sample - CORRECT ANSWER Members of the sample may choose not to respond.
Similar to Non Response.
Convenience sample - CORRECT ANSWER Participants are easy for researcher to access.
Tends to increase bias.
Cluster sample - CORRECT ANSWER Sample frame is divided into groups, we select a few
groups, then selecting ALL of the members of those groups.
Stratified sample - CORRECT ANSWER Sample frame is divided into groups. Then we choose
a random sample (usually the same size) from within EVERY group.
Multi-stage sample - CORRECT ANSWER Multiple rounds of randomness and grouping. For
example: randomly selecting a few groups, then choosing a small random sample just those
selected groups. Often a combination of Cluster and Stratified Sampling.
P(A)*P(B) - CORRECT ANSWER independent events: P(A and B) =
P(A|B) - CORRECT ANSWER P(A and B) ÷ P(B)
P(A or B) - CORRECT ANSWER P(A) + P(B) - P(A and B)
P(A and B) - CORRECT ANSWER P(A)*P(B|A)
Box plot - CORRECT ANSWER an image that has 5 number summary:
min, Q1, median, Q3, max,
nCr = n! / r!(n - r)! - CORRECT ANSWER probability combination formula
Boxplot - CORRECT ANSWER an image that has min, Q1, median, Q3, max
Histogram - CORRECT ANSWER A graphical representation -- bars, measuring the frequency
within each interval
Skewed right - CORRECT ANSWER Not a symmetric distribution, the tail is on the right, i.e.
extra stuff on the right
Measures of center - CORRECT ANSWER Median, the mean (and mode)
Measures of spread - CORRECT ANSWER Range, IQR & standard deviation
Standard Deviation Rule - CORRECT ANSWER 68% of the data are within 1 standard
deviation, 95% are within 2, 99.7 are within 3 standard deviations from the mean.
, For skewed data, use these for center and spread - CORRECT ANSWER In this situation, we
use median (for center) & IQR (for spread)
Explanatory variable - CORRECT ANSWER In a study, what we think is the "cause"
Response variable - CORRECT ANSWER In a study, what we think is the "effect"
Scatter plot - CORRECT ANSWER A graphical representation of Q -> Q
Two way table - CORRECT ANSWER A graphical representation of C -> C
Side-by side box - CORRECT ANSWER A graphical representation of C -> Q
Linear relationship - CORRECT ANSWER "shaped like a line"
Correlation coefficient, r - CORRECT ANSWER Between -1 and 1; measures how close the
points are to the line and if the trend is uphill (positive) or downhill (negative).
r = -0.2, for example - CORRECT ANSWER This is an example of a correlation coefficient that
represents a weak negative correlation.
r = 0.9, for example - CORRECT ANSWER This is an example of a correlation coefficient that
represents a strong positive correlation.
Linear regression line - CORRECT ANSWER A line that fits the data as close as possible, used
to make predictions
Interpolation - CORRECT ANSWER Making predictions *within* the range of your data. This
is usually accurate.
Extrapolation - CORRECT ANSWER Making predictions *outside* of the range of your data.
This is generally a bad idea.
Simpson's Paradox - CORRECT ANSWER When split up, each data set can have a pattern
which goes away when all the data is combined.
Only way to prove causation - CORRECT ANSWER Experiments, because they account for
lurking variables
Observational study - CORRECT ANSWER A type of study where we measure or survey
members of a sample without trying to affect them. Cannot prove causation.
Experimental study - CORRECT ANSWER A study where you split subjects up randomly and
impose a change on one group to study the effect; can prove causation
CORRECT ANSWERS| ACCURATE REAL EXAM WITH
FREQUENTLY TESTED QUESTIONS AND
RATIONALE|ALREADY A GRADED|GUARANTEED
PASS|LATEST UPDATE 2025.
Coefficient - CORRECT ANSWER A number by which a variable is being multiplied.
Coefficients are written in front of variables. 16x, 16 is coefficient. If there is no number you
assume an invisible1.
Term - CORRECT ANSWER Can be a single constant, a single, or a number of constants and
variables multiplied together.
Algebraic expression - CORRECT ANSWER String of terms connected by division, addition,
and subtraction.
How to write an algebraic expression - CORRECT ANSWER Constants at end. Write terms
with the largest exponents first. Always write in descending order of exponent value with
constants at the end.
Inverse operation - CORRECT ANSWER Operations that undo each other. Subtraction is
inverse of addition. Division is inverse of multiplication.
Like terms - CORRECT ANSWER Have the same variable with the same exponent
Degree of an expression - CORRECT ANSWER Refers to largest exponent in an expression
Linear - CORRECT ANSWER Has degree of 1
Quadratic - CORRECT ANSWER Has degree of 2
Cubic - CORRECT ANSWER Has degree of 3
Constant - CORRECT ANSWER Has degree of 0
Distributive property - CORRECT ANSWER Principle used to multiply a single term by
multiple terms. If there are parenthesis around multiple terms which are in turn multiplied by a
single term, we can use this property.
Histogram - CORRECT ANSWER A graphical representation -- bars, measuring the frequency
within each interval
Skewed right - CORRECT ANSWER Not a symmetric distribution, the tail is on the right
Measures of center - CORRECT ANSWER Median, the mean (and mode)
,Measures of spread - CORRECT ANSWER Range, IQR & standard deviation
Standard Deviation Rule - CORRECT ANSWER 68% of the data are within 1 standard
deviation,
95% are within 2,
99.7% are within 3 standard deviations from the mean.
median (for center) & IQR (for spread) - CORRECT ANSWER skewed data uses these for
center and spread
Scatter plot - CORRECT ANSWER A graphical representation of Q -> Q
Two way table - CORRECT ANSWER A graphical representation of C -> C
Side-by side box - CORRECT ANSWER A graphical representation of C -> Q
Interpolation - CORRECT ANSWER Making predictions *within* the range of your data. This
is usually accurate.
Extrapolation - CORRECT ANSWER Making predictions *outside* of the range of your data.
This is generally a bad idea.
Simpson's Paradox - CORRECT ANSWER When split up, each data set can have a pattern
which goes away when all the data is combined.
Prospective study - CORRECT ANSWER Is a study that's done over time to find results / A
study watching for outcomes during the study period
Unbalanced response - CORRECT ANSWER Giving more options that are negative than
positive options (or vice versa) which biases the responses towards the more common option
Matched pairs - CORRECT ANSWER Grouping two similar subjects and giving different
treatments/procedures to each in order to compare the differences. For example, having one twin
take a medication while the other twin does not.
Population - CORRECT ANSWER The entire group you are trying to describe or understand.
Sampling frame - CORRECT ANSWER List of group from which you choose your sample.
Sample - CORRECT ANSWER The group that is actually picked to be included in a study
Simple random sample - CORRECT ANSWER making a selection by following a random
pattern and selecting without replacement. Unbiased.
,Systematic sample - CORRECT ANSWER Sample is selected by listing the sampling frame,
then making a selection by following a simple pattern (eg. Every 20th name). Unbiased.
Voluntary sample - CORRECT ANSWER Members of the sample may choose not to respond.
Similar to Non Response.
Convenience sample - CORRECT ANSWER Participants are easy for researcher to access.
Tends to increase bias.
Cluster sample - CORRECT ANSWER Sample frame is divided into groups, we select a few
groups, then selecting ALL of the members of those groups.
Stratified sample - CORRECT ANSWER Sample frame is divided into groups. Then we choose
a random sample (usually the same size) from within EVERY group.
Multi-stage sample - CORRECT ANSWER Multiple rounds of randomness and grouping. For
example: randomly selecting a few groups, then choosing a small random sample just those
selected groups. Often a combination of Cluster and Stratified Sampling.
P(A)*P(B) - CORRECT ANSWER independent events: P(A and B) =
P(A|B) - CORRECT ANSWER P(A and B) ÷ P(B)
P(A or B) - CORRECT ANSWER P(A) + P(B) - P(A and B)
P(A and B) - CORRECT ANSWER P(A)*P(B|A)
Box plot - CORRECT ANSWER an image that has 5 number summary:
min, Q1, median, Q3, max,
nCr = n! / r!(n - r)! - CORRECT ANSWER probability combination formula
Boxplot - CORRECT ANSWER an image that has min, Q1, median, Q3, max
Histogram - CORRECT ANSWER A graphical representation -- bars, measuring the frequency
within each interval
Skewed right - CORRECT ANSWER Not a symmetric distribution, the tail is on the right, i.e.
extra stuff on the right
Measures of center - CORRECT ANSWER Median, the mean (and mode)
Measures of spread - CORRECT ANSWER Range, IQR & standard deviation
Standard Deviation Rule - CORRECT ANSWER 68% of the data are within 1 standard
deviation, 95% are within 2, 99.7 are within 3 standard deviations from the mean.
, For skewed data, use these for center and spread - CORRECT ANSWER In this situation, we
use median (for center) & IQR (for spread)
Explanatory variable - CORRECT ANSWER In a study, what we think is the "cause"
Response variable - CORRECT ANSWER In a study, what we think is the "effect"
Scatter plot - CORRECT ANSWER A graphical representation of Q -> Q
Two way table - CORRECT ANSWER A graphical representation of C -> C
Side-by side box - CORRECT ANSWER A graphical representation of C -> Q
Linear relationship - CORRECT ANSWER "shaped like a line"
Correlation coefficient, r - CORRECT ANSWER Between -1 and 1; measures how close the
points are to the line and if the trend is uphill (positive) or downhill (negative).
r = -0.2, for example - CORRECT ANSWER This is an example of a correlation coefficient that
represents a weak negative correlation.
r = 0.9, for example - CORRECT ANSWER This is an example of a correlation coefficient that
represents a strong positive correlation.
Linear regression line - CORRECT ANSWER A line that fits the data as close as possible, used
to make predictions
Interpolation - CORRECT ANSWER Making predictions *within* the range of your data. This
is usually accurate.
Extrapolation - CORRECT ANSWER Making predictions *outside* of the range of your data.
This is generally a bad idea.
Simpson's Paradox - CORRECT ANSWER When split up, each data set can have a pattern
which goes away when all the data is combined.
Only way to prove causation - CORRECT ANSWER Experiments, because they account for
lurking variables
Observational study - CORRECT ANSWER A type of study where we measure or survey
members of a sample without trying to affect them. Cannot prove causation.
Experimental study - CORRECT ANSWER A study where you split subjects up randomly and
impose a change on one group to study the effect; can prove causation
