1. The Terminology of Statistics
STT 2810
August 24, 2011
Mr. Caleb Marsh

2. Fundamentals
Data – observations (measurements, genders, survey responses, etc.) that have been collected.
Statistics (the science of) – a collection of methods for planning studies and experiments, obtaining data and then organizing, summarizing, presenting, analyzing, interpreting and drawing conclusions based on data.

3. Where do we get our data from?
Population – the complete collection of all elements (scores, people, measurements, etc.) to be studied. The collection is complete in the sense that it includes all subjects to be studied.

4. How do we get our data?
Census – the collection of data from every member of the population.
Sampling – a sub collection of members selected from the population.

5. What is all this data trying to describe?
Parameter – a numerical measurement describing some characteristic of a population.
Statistic – a numerical measurement describing some characteristic of a sample.
Ex – 95% of all ASU students possess a driver’s license
Parameter
Ex – A sample of 1087 voters showed that 10% are still undecided about how they will vote in the upcoming primaries.
Statistic

6. Types of Data
Qualitative Data – Can be separated into different categories that are distinguished by some non-numeric characteristic.
Also called categorical data.
Examples – Gender, Political Party Preference, Hair / Eye Color
Generally thought of as “word” responses.

7. Types of Data
Quantitative Data – Consists of numbers representing counts or measurements.
Height, Weight, IQ scores

8. Quantitative Data
Discrete Data – Occurs when the number of possible values is a finite (countable) number.
Continuous Data – Results from infinitely many possible values that correspond to some continuous scale that covers a range of values without gaps, interruptions or jumps.

9. Quantitative Data
Ex – The number of students registered for a class at a university.
Discrete
Ex – The ages of the students in that classroom.
Ex – The amount of gasoline used in a month.
Continuous
Ex – Miles driven by a motorist in a given day.
Ex – The number of cars currently owned in the US .