11 - Design Tools Flashcards
A factor or attribute that can assume two or more values : ___________________
A variable
T or F: variables can vary, variability is wonderful in some cases but not others
T
________ is all possible values that a variable can have
Domain
Smallest domain is ______
2 (dichotomous, binary)
Properties that vary in a type of attribute (ex: sex, religion, eye color, marital status): _________
Qualitative variable
Properties that are different in amount (ex: weight, height, blood pressure): __________
Quantitative variable
Explain what are discrete variables:
Quantitative adjacent variable, in which no intermediate values are possible
Explain what are continuous variables;
Intermediate values are possible in between two adjacent scale values (ex: weight, height, blood pressure)
T or F: in practice continuous variables are converted to discrete variables
T
The independent variable is on the __ axis and the dependent variable is on the __ axis
x
y
Presumed causal factor in a cause-effect relationship, in an experiment, this is what you manipulate:
independent variable
Presumed effect in a cause-effect relationship, in an experiment, this is the outcome you measure (Y-axis)
dependent variable
A 3rd variable to explain why the two are linked …. lies on the causal pathway: ______________
mediator variable
Variable that alters the strength of the relationship, aka interaction terms or effect modification:
moderating variable
Variable (C) that correlates both with X and Y, not in the causal pathway, causes confusion in the true relationship: __________
confounding variable
T or F: Scientists need to be explicit on how they define their variables
T
A process of systematically assigning values to variables: __________
Measurement
Measurement scales: ____________________
Organization + math
___________: qualitative differences in scale values. Sex, politics, college major, food categories, menu offerings, hair color
Nominal
___________: different scale values represent relative differences, and the order matters. Ex: rank ice cream preferences
Ordinal
_________: scale values have equal and exact distance. Temperature, time of day, calendar year
Interval
_________: interval but has an absolute zero. Time, length, annual income, caloric intake, pregnancies, money, etc. True ratios can be calculated
Ratio
Nominal and ordinal scales are considered ______________________ scales
qualitatives, categorical
Interval and Ratios are considered ___________scales
quantitative
The degree to which the measurement yields results that agree with the truth:
Accuracy (validity)
The degree to which the measurement yields a consistent value:
Reliability (precision)
Why is the accuracy of food labels important:
Because it is useful for individuals to monitor caloric intake
____________________: all cases or observations of interest
Population (universe)
____________: a subset of cases or observations
Sample
____________: a list from which samples will be selected
sample frame
________: characteristic of the population
parameter
________ : characteristic of the sample
statistic
What does the NHANES US survey stands for:
National Health and Nutrition Evaluation survey
CHMS:
Canadian Health Measure Survey
Why CHMS biomonitor?
- Establish reference ranges to enable deeper studies of sub-populations or across countries
- Establish baseline levels to assess over-time changes
- Help set priorities/take action
- Assess effectiveness of regulatory decisions
- Support research on links between exposure and health effect
