Statistics Phase 1

Statistics

collecting, organizing, interpreting

Descriptive Statistics

Summarize data, Organize data, Describe what you already collected

Descriptive Statistics includes

mean, median, mode, graphs, standard deviation

Inferential Statistics

make predictions, test hypotheses, draw conclusion about a population from a sample

Inferential Statistics

t-tests, ANOVA, correlation, regression, chi-square

Population

entire group

Sample

smaller group taken from population (selected, subset, or portion)

Qualitative (Categorical)

Names, Labels, Groups, NO MATH (gender, diagnosis, blood type, education level)

Quantitative (Numerical)

Real numbers, you can average, use formulas (height, weight, age, bp, test scores)

Nominal

names (gender, blood type)

Ordinal

ranked (pain scale, class rank)

Interval

equal spacing, no true zero (temperature (°F)

Ratio

equal spacing + true zero (weight, height, age)

Research question

“______ must relate to the date that will be collected”

Variable

what is being measured

Null H0

no difference, no effect

Research H1

There IS a difference, effect, or relationship

Critical region

The values are so extreme that they are unlikely if the null hypothesis is true

Inside critical region

reject H0

Outside critical region

reject H0

Experimental study

researcher controls a variable

Non experimental study

observes only (no manipulation)

Bell curve

test scores, bp, heights, lab values

critical value

the cutoff number that separates “normal” values from “extreme” values

fail to reject h0 if in the middle region