WPC 300 REVISION EXAM PAPER 2026/2027 QUESTIONS
AND SOLUTIONS RATED A+
✔✔Continuous - ✔✔If a random variable can take an infinite number of distinct values,
then it is
✔✔Independent variable - ✔✔the one that is changed by the scientist
✔✔Dependent variables - ✔✔the things that the scientist focuses his or her
observations on to see how they respond to the changes made to the independent
variables
✔✔Controlled variables - ✔✔quantities that a scientist want to remain constant
✔✔Covariance - ✔✔is a measure of the linear association between two variables, X and
Y. Like the variance, the different formulas are used for populations and samples
✔✔Correlation - ✔✔a measure of the linear relationship between two variables, X and
Y, which does not depend on the units of measurement
✔✔Random Sampling - ✔✔Select a group of subjects (a sample) for a study from a
larger group (a population)
✔✔Hypothesis testing - ✔✔a procedure based on sample evidence and probability,
used to test claims regarding a characteristic of one or more populations
✔✔Observational Studies - ✔✔The population/sample is observed without any
interference or intervention by the investigator
✔✔Experimental Studies - ✔✔The investigator tries to control the environment in which
the hypothesis is tested
✔✔Treatments - ✔✔Different procedures we want to compare
✔✔Experimental Units - ✔✔Things to which we apply the treatment
✔✔Responses - ✔✔The outcomes that we observe after applying a treatment to an
experimental unit
✔✔Randomization - ✔✔Use of a known, understood probabilistic mechanism for the
assignment of treatment to units
✔✔Experimental Error - ✔✔Random variation present in all experimental results
, ✔✔Measurement Units - ✔✔Actual objects on which the response is measured
✔✔Blinding - ✔✔Occurs when the evaluator of response do not know which treatment
was given to each unit
✔✔Control - ✔✔Treatment is a "standard" treatment that is used as a baseline for the
other treatment
✔✔Placebo - ✔✔Is a null treatment that is used when the act of applying a treatment,
any treatment, has an effect
✔✔Factors - ✔✔Combine to form treatment. Individual setting for each factor are called
levels of the factor
✔✔Block - ✔✔The arranging of experimental units in groups (blocks) that are similar to
one another
✔✔Confounding - ✔✔Occurs when the effect of one factor or treatment cannot be
distinguished from that of another factor or treatment
✔✔A/B Testing - ✔✔A method of comparing two versions of a web page or app against
each other to determine which one performs better
✔✔placebo effect - ✔✔experimental results caused by expectations alone; any effect
on behavior caused by the administration of an inert substance or condition, which the
recipient assumes is an active agent.
✔✔Data Mining - ✔✔The nontrivial process of identifying valid, novel, potentially useful,
and ultimately understandable patterns in data stored in structured databases
✔✔Unsupervised - ✔✔no knowledge of output, class or value, data is unlabeled or
value is unknown
✔✔Supervised - ✔✔knowledge of output, data is labeled with class or value
✔✔Association - ✔✔a data mining function that discovers the probability of the co-
occurence of items in a collection
✔✔Cluster Analysis - ✔✔Grouping data so that elements in a group will be
Similar (or related) to one another
Different (or unrelated) from elements in other groups
✔✔Partition - ✔✔Non-overlapping subsets (clusters) such that each data object is
exactly one subset
AND SOLUTIONS RATED A+
✔✔Continuous - ✔✔If a random variable can take an infinite number of distinct values,
then it is
✔✔Independent variable - ✔✔the one that is changed by the scientist
✔✔Dependent variables - ✔✔the things that the scientist focuses his or her
observations on to see how they respond to the changes made to the independent
variables
✔✔Controlled variables - ✔✔quantities that a scientist want to remain constant
✔✔Covariance - ✔✔is a measure of the linear association between two variables, X and
Y. Like the variance, the different formulas are used for populations and samples
✔✔Correlation - ✔✔a measure of the linear relationship between two variables, X and
Y, which does not depend on the units of measurement
✔✔Random Sampling - ✔✔Select a group of subjects (a sample) for a study from a
larger group (a population)
✔✔Hypothesis testing - ✔✔a procedure based on sample evidence and probability,
used to test claims regarding a characteristic of one or more populations
✔✔Observational Studies - ✔✔The population/sample is observed without any
interference or intervention by the investigator
✔✔Experimental Studies - ✔✔The investigator tries to control the environment in which
the hypothesis is tested
✔✔Treatments - ✔✔Different procedures we want to compare
✔✔Experimental Units - ✔✔Things to which we apply the treatment
✔✔Responses - ✔✔The outcomes that we observe after applying a treatment to an
experimental unit
✔✔Randomization - ✔✔Use of a known, understood probabilistic mechanism for the
assignment of treatment to units
✔✔Experimental Error - ✔✔Random variation present in all experimental results
, ✔✔Measurement Units - ✔✔Actual objects on which the response is measured
✔✔Blinding - ✔✔Occurs when the evaluator of response do not know which treatment
was given to each unit
✔✔Control - ✔✔Treatment is a "standard" treatment that is used as a baseline for the
other treatment
✔✔Placebo - ✔✔Is a null treatment that is used when the act of applying a treatment,
any treatment, has an effect
✔✔Factors - ✔✔Combine to form treatment. Individual setting for each factor are called
levels of the factor
✔✔Block - ✔✔The arranging of experimental units in groups (blocks) that are similar to
one another
✔✔Confounding - ✔✔Occurs when the effect of one factor or treatment cannot be
distinguished from that of another factor or treatment
✔✔A/B Testing - ✔✔A method of comparing two versions of a web page or app against
each other to determine which one performs better
✔✔placebo effect - ✔✔experimental results caused by expectations alone; any effect
on behavior caused by the administration of an inert substance or condition, which the
recipient assumes is an active agent.
✔✔Data Mining - ✔✔The nontrivial process of identifying valid, novel, potentially useful,
and ultimately understandable patterns in data stored in structured databases
✔✔Unsupervised - ✔✔no knowledge of output, class or value, data is unlabeled or
value is unknown
✔✔Supervised - ✔✔knowledge of output, data is labeled with class or value
✔✔Association - ✔✔a data mining function that discovers the probability of the co-
occurence of items in a collection
✔✔Cluster Analysis - ✔✔Grouping data so that elements in a group will be
Similar (or related) to one another
Different (or unrelated) from elements in other groups
✔✔Partition - ✔✔Non-overlapping subsets (clusters) such that each data object is
exactly one subset
