Intro to Stat
This “group” is usually referred to as a
What is a population (or, sometimes, population of interest).
A ____________ __________ is a sample obtained by selecting individuals in the population that are easiest to reach
What is a convenience sample
__________ occurs when a certain group of individuals in the target population is not included in the sampling frame and therefore given no chance of selection in the sample.
What is Undercoverage
In an _________ _______, we measure individuals in the sample without trying to affect them.
What is an observational study
A ___ ______ represents each category as a bar
What is a bar graph
A model that explains all possible values of the variable and the likelihood of observing each value
What is Distribution
A __________ __________ sample consists of the people who choose to respond to a broad invitation
What is a voluntary response
________ occurs when individuals selected for the sample cannot be contacted or refuse to participate in the study
What is Nonresponse
The explanatory/independent variables are commonly referred to as
What are factors
What are the two ways to evaluate the center spread
What is mean and median
When quantitative variables have an uncountably infinite number of outcomes..
What is continuous
What are the three unbiased sampling options?
What is Simple random sample (SRS), Stratified random sample, and Cluster sampling
_________ ______ occurs when individuals in the target population are not sampled at an equal rate
What is Selection bias
A _____ is a group of subjects known to be similar in some way that is thought to influence the response variable.
What is a block
How many peaks does each have?
Unimodal:
Bimodal:
Multimodal:
one peak
two peak
multiple peaks
When quantitative variables have a finite or countably infinite number of outcomes they are known as...
What is Discrete
A ________ __________ describes exactly how to choose a sample from the sampling frame
What is a sampling design
_________ is a procedure that allows us to place a higher or lower emphasis on certain individuals in the sample.
What is Weighting
What are the three common experimental designs
What is
• Randomized comparative experiments
• Randomized block experiments
• Matched pairs experiments
List the methods of visualizing quantitative distributions:
What is Histogram, Stemplot (Stem-and-leaf plot), Boxplot, Time plot
When you assign individuals in the population into one of several groups or categories
What are Categorical variables
A _______ is a subset of individuals in the population who are grouped because they share a common characteristic believed to affect the variable of interest. A _______ is believed to be a representative group from the population, not grouped by any feature believed to affect the variable of interest.
What is stratum; cluster
When the probability of nonresponse is the same for all individuals in the sample, we say that the nonrespondents are missing completely at random.
What is Missing completely at random (MCAR)
The experimental design is defined by four principles:
What is
1. Control
2. Replication
3. Blocking
4. Randomness
When describing the distribution of a quantitative variable (in a histogram or stemplot), we focus on the following descriptors:
What is shape, center, and spread