Term

Definition
 Qualitative variables  No special order 


Term

Definition
categories have an order  distance between categories unknown (ie Dem Mod Rep) 


Term

Definition
Numerical values with known, meaningful distances  (monetary values) (percentages) 


Term
3 Objectives of Statistics 

Definition
Designhow to answer the research Q Description  (what does the data mean) Inference (predictions, external validity) 


Term

Definition
Inferring individuallevel relationships from aggregatelevel results. 


Term

Definition


Term

Definition


Term

Definition
the degree to which an instrument consistently measures a concept 


Term

Definition
the degree to which a measure is likely to produce a concept’s true value 


Term
4 steps of operationalization 

Definition
1) Clarify the Concept 2) Operationalize the concept as something measurable and concrete 3) Gather Data 4) Construct Variables 


Term

Definition


Term

Definition
A graph that displays the data by using vertical bars of various heights, where the heights represent the frequencies 


Term

Definition
The mean is sensitive to the influence of a few extreme observations
Also, a skewed distribution (with or without outliers) will pull the mean towards its long tail 


Term

Definition
The middle of the data (i.e. the 50th percentile) Put the data in order, then choose the central data point If n is even, take the mean of the middle two data points 


Term

Definition
The most frequently occurring value The most likely outcome among your data values 


Term

Definition
limits the influence of outliers and its value does not respond strongly to changes in a few observations (no matter how large) 


Term

Definition
The most common measure The standard deviation is approximately equal to “how much the average observation differs from the mean” When this number is big, we’d say the average observation tends to lie far from the mean the data are very spread out 


Term

Definition
About 68% of the data will fall within 1 standard deviation of the sample mean About 95% will fall within 2 standard deviations Nearly all data will fall within 3 standard deviations 


Term

Definition
is a numerical measure of the likelihood that a specific event will occur. 


Term
4 assumptions of standard normal distribution 

Definition
1) The total area under the curve is 1.0. 2) The curve is symmetric about the mean. 3) The two tails of the curve extend indefinitely. 4) Empirical Rule (covered last class): appx 68% 95% 99% of observations fall within 1, 2, and 3 standard deviations from the mean respectively 


Term
standard normal distribution 

Definition
The normal distribution with μ = 0 and σ = 1 

