IDS 270 COMPREHENSIVE QUESTIONS AND
ANSWERS SURE A+
✔✔For two variables at a time, what types of graphs/tables are categorical?
What chapter does this relate to? - ✔✔Two way table and their graphs?
Chapter 2
✔✔For two variables at a time, what type of graph/table is quantitative? - ✔✔Scatterplot
✔✔For two variables at a time, what type of numbers/computations are categorical? -
✔✔%'s from two-way charts
✔✔For two variables at a time, what type of numbers/computations are quantitative? -
✔✔Correlations, regression slope
✔✔Conditional Probability formula - ✔✔P(B|A)= P(A and B) / P(A)
✔✔Disjoint definition - ✔✔Two events that are mutually exclusive that cannot occur at
the same time.
✔✔What a synonym for disjoint? - ✔✔Mutually exclusive
✔✔Independent probability definition - ✔✔Two events are not mutually exclusive and
can occur at the same time
✔✔Define: observational study - ✔✔Observing behavior or ask people questions as
they are going about their day to day lives. Ex: Call people and ask them how often they
eat out
, ✔✔Define: experiment - ✔✔Imposing some treatment on people and then observe their
behavior or ask questions Ex. Give people a drug and then do chemical analysis of their
blood
✔✔Define: confounded variables - ✔✔Two variables where the effect of one on the
dependent variable cannot be separated from the effect of the other ex. If you take
drugs and drink alcohol and then have a car accident, the effect of the drugs vs. the
alcohol cannot be separated from each other as the cause of the accident
✔✔Define: Population - ✔✔Set of everything
✔✔Define: Sample - ✔✔Small group pulled from population
✔✔Define: Bias (another definition different from other one in these flashcards) -
✔✔Systematically favoring a certain outcome for research.
✔✔Define: Simple random sampling - ✔✔Labeling all in population with a number and
computer selects a random set of numbers. Therefore everyone has an equal chance of
being in sample
✔✔Define: Stratified sampling - ✔✔Breaking the population into natural segments
(strata) and then using random sampling within the strata. Ex. Radio Stations or types of
colleges. (private colleges, public universities etc).
✔✔Define: natural segments - ✔✔strata
✔✔Define: Multi-stage sampling - ✔✔Repeatedly practicing stratified sampling to get a
final sample
✔✔Define: undercoverage - ✔✔Where some in the population cannot be selected for
the sample ex. people without phones if one is collecting data over the phone
✔✔Define: treatment - ✔✔A unique combo of levels of factors given to a set of subjects
✔✔Define: placebo effect - ✔✔When a subject thinks they are feeling an effect because
they are simply involved in the study
✔✔Define: Completely randomized design - ✔✔Within an experiment, use random
sampling to assign the subjects to the different treatments
✔✔Define: Statistical significance - ✔✔A finding that is unlikely to be due to random
chance alone
ANSWERS SURE A+
✔✔For two variables at a time, what types of graphs/tables are categorical?
What chapter does this relate to? - ✔✔Two way table and their graphs?
Chapter 2
✔✔For two variables at a time, what type of graph/table is quantitative? - ✔✔Scatterplot
✔✔For two variables at a time, what type of numbers/computations are categorical? -
✔✔%'s from two-way charts
✔✔For two variables at a time, what type of numbers/computations are quantitative? -
✔✔Correlations, regression slope
✔✔Conditional Probability formula - ✔✔P(B|A)= P(A and B) / P(A)
✔✔Disjoint definition - ✔✔Two events that are mutually exclusive that cannot occur at
the same time.
✔✔What a synonym for disjoint? - ✔✔Mutually exclusive
✔✔Independent probability definition - ✔✔Two events are not mutually exclusive and
can occur at the same time
✔✔Define: observational study - ✔✔Observing behavior or ask people questions as
they are going about their day to day lives. Ex: Call people and ask them how often they
eat out
, ✔✔Define: experiment - ✔✔Imposing some treatment on people and then observe their
behavior or ask questions Ex. Give people a drug and then do chemical analysis of their
blood
✔✔Define: confounded variables - ✔✔Two variables where the effect of one on the
dependent variable cannot be separated from the effect of the other ex. If you take
drugs and drink alcohol and then have a car accident, the effect of the drugs vs. the
alcohol cannot be separated from each other as the cause of the accident
✔✔Define: Population - ✔✔Set of everything
✔✔Define: Sample - ✔✔Small group pulled from population
✔✔Define: Bias (another definition different from other one in these flashcards) -
✔✔Systematically favoring a certain outcome for research.
✔✔Define: Simple random sampling - ✔✔Labeling all in population with a number and
computer selects a random set of numbers. Therefore everyone has an equal chance of
being in sample
✔✔Define: Stratified sampling - ✔✔Breaking the population into natural segments
(strata) and then using random sampling within the strata. Ex. Radio Stations or types of
colleges. (private colleges, public universities etc).
✔✔Define: natural segments - ✔✔strata
✔✔Define: Multi-stage sampling - ✔✔Repeatedly practicing stratified sampling to get a
final sample
✔✔Define: undercoverage - ✔✔Where some in the population cannot be selected for
the sample ex. people without phones if one is collecting data over the phone
✔✔Define: treatment - ✔✔A unique combo of levels of factors given to a set of subjects
✔✔Define: placebo effect - ✔✔When a subject thinks they are feeling an effect because
they are simply involved in the study
✔✔Define: Completely randomized design - ✔✔Within an experiment, use random
sampling to assign the subjects to the different treatments
✔✔Define: Statistical significance - ✔✔A finding that is unlikely to be due to random
chance alone
