Data
Study that involves the collection, organization, description, analysis, and interpretation of data
Statistics
Variables that are typically integers representing a count of objects or abstract amounts
Discrete (variables)
Type of sample that involves a researcher taking the "easy way" when collecting data
Convenience sample
In Statistics, we analyze characteristics of an entire group of individuals by collecting and analyzing data from smaller subgroups of the whole group.
These small subgroups are known as _________.
Samples
Data in its original form
Raw Data
The type of variables used in a Likert scale: Below Average, Average, Above Average, etc.
Ordinal (variables)
Type of sample that involves separating population into clusters and selecting random members from each cluster
Stratified random sample
You'd like to know the proportion(%) of seniors at THS that are going to attend prom, so you randomly survey 50 of them asking if they are going. Identify the population and the sample.
Population = All THS seniors
Sample = 50 surveyed seniors
Data that is organized into rows and columns for easier analysis
Structured Data
Type of variable representing your birth year
Discrete
The type of sample that is the most ideal, where each member of the population has an equal likelihood of being selected
Simple random sample
You'd like to know the proportion(%) of seniors at THS that are going to attend prom, so you randomly survey 50 of them asking if they are going. Identify the parameter and the statistic.
Parameter= % of ALL seniors attending prom
Statistic= % of SAMPLED seniors attending prom
What does each column in a data set represent?
The variables
Explain the difference between nominal and ordinal data.
Nominal= cannot be ordered (in a linear way)
Ordinal=can be ordered in a obvious (linear) way
This can show up anytime a sample is collected in a way that does not accurately represent the population it was collected from.
Bias
We'd like to know what % of Texas households own a dog. So we sample 100 of them and find that 47% of them own a dog. Identify the population and the parameter.
Population= All Texas households
Parameter= % of ALL Texas households that own a dog (unknown)
An attempt to make a prediction based on the data we collect and analyze
Inference
Things like Social Security number, credit card number, and phone number would be considered what type of variable?
Nominal (They're numbers, but not used in a mathematical way.)
The natural variation from sample to sample that happens by chance. It cannot be avoided.
Sampling error
We'd like to know what % of Texas households own a dog. So we randomly sample 100 of them and find that 47% of them own a dog. Identify the sample and the statistic.
Sample= 100 households
Statistic= 47% (that own a dog)