Chapter 7 Hypotheticals and You: Testing Your

Questions

Part IIITaking Chances for Fun and Profit

What is a hypothesis?

An “educated guess”

Their role is to reflect the general problem statement or question that is driving the research

Translates the problem or research question into a form that can be tested.

Samples and Populations

PopulationThe large group to which you would like to

generalize your findings Sample

The smaller, representative group of the population that is used to do the researchSampling error – a measure of how well a sample

represents the population“Generalizability of the sample”

The Null Hypothesis

Statements that two or more things are equal or unrelated to each other

H0 : m1 = m2

The starting pointAccepted as true without knowing more

informationBenchmark with which actual outcomes are

compared

The Research Hypothesis

Statement that there is a relationship between two variables

Two Types…Nondirectional -- H1 : X1 ≠ X2

Reflects a difference; direction is not specifiedTwo-tailed test

Directional -- H1 : X1 > X2Reflects a difference; direction is specifiedOne-tailed test

Null & Research Hypotheses

What Makes a Good Hypothesis?

Stated in a declarative form rather than a question“Females are taller than males at age 13”Not “Are females taller than males at age 13?”

Defines an expected relationship between variables

Reflects the theory or literature on which they are based (Google scholar)

Brief and to the pointTestable – includes variables that can be

measured and results than can be statistically verified.

Is interesting and NEW knowledge!