3.1 Flashcards
What is a random variable?
This is a function that represents a set of numbers and there is a probability associated with a number being picked from the sample space.
What is an observation?
This is an individual occurrence.
What is the data?
This is the recorded information of one or more variables for a set of observations.
What is the dataset?
This is a particular set of data.
What is the nominal scale?
These are observations that are categorized into groups that cannot be ranked or ordered.
What is the ordinal scale?
These are observations that are categorized into groups that can be ranked or ordered.
What is the interval scale?
The most you can do with this scale is subtract the values.
What is the ratio scale?
This scale is also only quantitatively useful.
What is the mean?
This is the average of the data and it is used to gauge the data surrounding it.
What is the proportion?
This is a ratio of the category over the total observations.
What is the population?
These are the set of instances that are associated with the variable of interest.
What is the sample?
This is the selected subset of observations from the population.
What are the parameters?
These are the means or proportions at the population level.
What are the sample statistics?
These are the sample level means and proportions.
What is simple random sample?
This is a random selection of objects from a size n.
What is stratified sampling?
This is when the sample is divided into subgroups based on observations or characteristics and randomly selects X objects overall.
What is cluster sampling?
The objects of interest that are chosen are randomly picked from subgroups that are not that different from each other.
What is systematic sampling?
This is when a specific number on a list of the sample space is chosen.
What is convenience sampling?
This is when the objects of interest are chosen based on ease of attaining.
What is voluntary sampling?
This is when people are the subjects of interest and they volunteer to be in the sample.
What is sample bias?
This is when the subset of the population has a higher or lower chance of being selected for a sample compared to the rest of the population.
What is non-response bias?
For whatever reason some portion of the sample’s response is not recorded.
What is measurement bias?
This is when the response recorded from the sample is not true.
What is an explanatory variable?
This is the variable that is able to cause changes to another variable.
What is the response variable?
This is the variable that responds and changes due to the explanatory variable.
What is the treatment group?
This group contains the observations in the sample and receives exposure.
What is the control group?
This group contains the observations in the sample however it does not receive exposure.
What is a placebo?
This is when there is a group that receives the treatment while another group receives the inactive treatment thus it becomes a psychological test.
What is the single-blind design?
The subjects do not know which group they belong to.
What is a double bind design?
This is when in both groups the subjects do not know which group they belong to.
What is the lurking variable?
This is the variable that can affect the response of the variable but is not taken into account into the design of the experiment.
What is the median?
This is the number in the middle when ordered from smallest to largest.
What is variance?
This is the spread of the values from the mean or average value.
