Why Study Statistics
Why is studying statistics important in research?
It helps organize data into a usable and interpretable form.
What is the difference between an independent and dependent variable?
An independent variable is manipulated, while a dependent variable is measured.
What is the lowest level of measurement?
Nominal scale.
What is the difference between a population and a sample?
A population includes all individuals of interest; a sample is a subset used for study.
What is the key feature of an experimental design?
Random assignment of participants to conditions.
Give an example of a claim that can be evaluated using statistics.
"4 out of 5 dentists recommend Colgate."
We want to know if different fruit supplements affect the amount of weight mice gain in 6 months, what is the independent variable?
The different fruit supplements.
Which scale allows ordering of items but does not have equal intervals?
Ordinal scale.
What is simple random sampling?
Every member of the population has an equal chance of being selected.
What makes a quasi-experimental design different from an experimental design?
It lacks random assignment.
How does statistics help us become better consumers?
By allowing us to critically evaluate numerical claims and research findings.
We want to know if 0 mg, 50 mg, or 100 mg of vitamin D has an affect on cancer symptoms, what is the dependent variable?
Cancer symptoms.
Give an example of a variable that would be considered interval and why.
Credit score, because it is ordered, has equal intervals between the scores, and no true 0.
What is an example of convenience sampling?
Surveying students on a college campus who are easily accessible.
What type of research design observes variables without manipulation?
Non-experimental design.
What is the role of statistics in linking research ideas to usable conclusions?
It provides a systematic way to analyze and interpret data.
What is the key difference between discrete and continuous variables?
Discrete variables have countable values; continuous variables have infinite possible values within a range.
What level of measurement do each of these variables belong to: Kelvin, colors, SAT scores, places in a race?
In order: ratio, nominal, interval, ordinal.
A researcher selects schools from different regions and surveys all students within selected schools. What sampling method is this?
Cluster sampling.
What is the difference between descriptive and inferential statistics?
Descriptive statistics summarize data; inferential statistics allow conclusions beyond the sample.
How can statistical knowledge help in understanding persuasive techniques?
It helps analyze numerical claims and determine their validity.
Name an example of a qualitative and a quantitative variable.
Qualitative—eye color; Quantitative—reaction time.
How does the level of measurement influence the statistical tests we use?
Different levels determine which mathematical operations and statistical analyses are meaningful.
What type of sampling involves participants recruiting others from their network?
Snowball sampling
A researcher finds that gratitude practice increases happiness and claims causation. Which type of statistics is this?
Inferential statistics.