Boxplot - ANSWERSan image that has min, Q1, median, Q3, max
Histogram - ANSWERSA graphical representation -- bars, measuring the frequency within each
... [Show More] interval
Skewed right - ANSWERSNot a symmetric distribution, the tail is on the right, i.e. extra stuff on the right
Measures of center - ANSWERSMedian, the mean (and mode)
Measures of spread - ANSWERSRange, IQR & standard deviation
Standard Deviation Rule - ANSWERS68% 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 - ANSWERSIn this situation, we use median (for center) & IQR (for spread)
Explanatory variable - ANSWERSIn a study, what we think is the "cause"
Response variable - ANSWERSIn a study, what we think is the "effect"
Scatter plot - ANSWERSA graphical representation of Q -> Q
Two way table - ANSWERSA graphical representation of C -> C
Side-by side box - ANSWERSA graphical representation of C -> Q
Linear relationship - ANSWERS"shaped like a line"
Correlation coefficient, r - ANSWERSBetween -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 - ANSWERSThis is an example of a correlation coefficient that represents a weak negative correlation.
r = 0.9, for example - ANSWERSThis is an example of a correlation coefficient that represents a strong positive correlation.
Linear regression line - ANSWERSA line that fits the data as close as possible, used to make predictions
Interpolation - ANSWERSMaking predictions *within* the range of your data. This is usually accurate.
Extrapolation - ANSWERSMaking predictions *outside* of the range of your data. This is generally a bad idea.
Simpson's Paradox - ANSWERSWhen split up, each data set can have a pattern which goes away when all the data is combined.
Only way to prove causation - ANSWERSExperiments, because they account for lurking variables
Observational study - ANSWERSA type of study where we measure or survey members of a sample without trying to affect them. Cannot prove causation.
Experimental study - ANSWERSA study where you split subjects up randomly and impose a change on one group to study the effect; can prove causation
Prospective study - ANSWERSIs a study that's done over time to find results / A study watching for outcomes during the study period
Retrospective study - ANSWERSA study that looks backwards to assess outcomes and possible causes after the fact
Control group - ANSWERSrandomly assign people or things to groups. One group receives a treatment and the other group does not. This is the group that does not receive treatment
Placebo - ANSWERSA substance or procedure that has no effect used for comparison to the real substance or procedure
Placebo effect - ANSWERSA beneficial effect produced by the belief of the patient/subject, not by the intervention itself.
Experimenter effect - ANSWERSWhen the persons running an experiment affects its results by influencing the subjects inadvertently
Open question - ANSWERSA question that gives the responder freedom to answer in many different ways -- harder to analyze with statistics.
Closed question - ANSWERSA question with limited choices, e.g. multiple choice or yes/no. Easier to analyze statistically.
Unbalanced response - ANSWERSGiving more options that are negative than positive options (or vice versa) which biases the responses towards the more common option
Matched pairs - ANSWERSGrouping 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.
Blind experimental study - ANSWERSWhen information of a study isn't revealed to the participants
Double Blind Study - ANSWERSWhen information of study is hidden from the researcher and the participant.
Population - ANSWERSThe entire group you are trying to describe or understand.
Sampling frame - ANSWERSList of group from which you choose your sample.
Sample - ANSWERSThe group that is actually picked to be included in a study
Simple random sample - ANSWERSmaking a selection by following a random pattern and selecting without replacement. Unbiased.
Systematic sample - ANSWERSSample is selected by listing the sampling frame, then making a selection by following a simple pattern (eg. Every 20th name). Unbiased.
Voluntary sample - ANSWERSMembers of the sample may choose not to respond. Similar to Non Response.
Convenience sample - ANSWERSParticipants are easy for researcher to access. Tends to increase bias.
Cluster sample - ANSWERSSample frame is divided into groups, we select a few groups, then selecting ALL of the members of those groups.
Stratified sample - ANSWERSSample frame is divided into groups. Then we choose a random sample (usually the same size) from within EVERY group.
Multi-stage sample - ANSWERSMultiple 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.
The formula for all simple probabilities - ANSWERS(number of possible outcomes for the specific event) / (total number of possible outcomes)
For independent events, P(A and B) = ? - ANSWERSP(A)*P(B)
For independent events, P(A|B) = ? - ANSWERSP(A) [this is the right side of which probability formula?]
P(A|B) = ? - ANSWERSP(A and B) ÷ P(B)
P(A or B) = ? - ANSWERSP(A) + P(B) - P(A and B)
In general, P(A and B) = ? - ANSWERSP(A)*P(B|A) [Show Less]