Studies and Bias
This can occur when participants volunteer to be included in a sample.
Self-Selection Bias
The percent of free throws made is an example of this type of variable.
Quantitative
This is a subset of the population on which we collect data.
Sample
This is the sum of all of the data, divided by the number of data points.
Mean
What are three different measures of dispersion?
IQR, Range, Variance, Standard Deviation
This occurs when a sample is collected in such a way that it does not represent the population of interest.
Sampling Bias
A researcher wants to assess the effect of GDP on how well a country performs in the FIFA World Cup. What are the response and predictor variables in this study?
Predictor: GDP
Response: Performance in World Cup
A numeric summary of a variable, pertaining to a sample.
Statistic
What are three different measures of location?
Mean, Median, Quartiles, Maximum, Minimum
Describe in words what variance measures.
How spread out the data is from the mean.
This method to collect a sample reduces bias.
Random Sampling
Shoe size is an example of this type of variable.
Categorical
The entire collection of a group we are interested in studying.
Population
This measure of center is resistant to outliers.
Median
Which is greater: range or IQR?
Range
In this type of statistical study, there is no manipulation of the participants by the researcher.
Observational Study
If not taken into account, this type of variable can lead us to think that there is a causal relationship between our predictor and response, when in reality, there is not.
Confounding Variable
This is an unknown number that is a numerical summary of a variable, pertaining to a population.
Parameter
Consider the data (1, 4, 5, 15). Which number, if added to the data, would decrease the mean?
A. 6 B. 6.5 C. 7 D. 7.5
A. 6
Describe the relationship between variance and standard deviation.
SD2 = Var
SD = sqrt(Var)
This is a solution to the placebo effect and experimenter effect.
Blinding
Changes in one variable that can be explained by another variable.
Explained Variation
This is the process of making generalizations of the population based on our sample.
(Statistical) Inference
Calculate the 5-number summary for the following data: (4, 2, 5, 6, 11, 6, 8)
(2, 4, 6, 8, 11)
Consider a variable with a mean of 5 and a standard deviation of 1. What is a number that could be added to our data that would increase the mean but decrease the standard deviation?
A. 3 B. 4.9 C. 5.1 D. 7
C. 5.1