Hypotheses Flashcards
define hypothesis
- a precise, testable statement of what the researchers PREDICT will be the outcome of the study
what does a hypothesis usually involve?
proposing a possible relationship between the IV & DV
what is a convention in research?
that the hypothesis is written in 2 forms:
1) the null hypothesis
2) the alternative hypothesis
the 4 types of research hypotheses
1) alternative
2) null
3) the 1 tailed directional
4) the 2 tailed non directional
alternative hyptheses
states that there’s a relationship between the 2 variables being studied
i.e. one has an effect on the other
states that the results are NOT due to chance & thus are SIGNIFICANT in supporting the theory being investigated
what is an AH sometimes called?
an experimental hypothesis
when?
when the method of investigation= experiment
null hypothesis
states that there’s NO relationship between the 2 variables being studied
i.e. 1 variable does NOT affect the other
states that the results are due to CHANCE and are thus INSIGNIFICANT in supporting the theory being investigated
ND hypothesis
- a 2 tailed ND predicts that the IV WILL have an affect on the DV but the direction of the effect= NOT specified
example of an ND hypothesis
- there will be a difference in how many numbers are correctly recalled by the adults
Directional hypothesis
- a 1 tailed DH predicts the NATURE of the IV on the DV
example of a DH
- adults will recall MORE words than kids
So can a hypothesis be PROVEN?
- upon analysis of the results, an AH can be rejected/ supported but it can never be proven to be correct
what must you avoid when referring to results?
- any reference to results PROVING a theory as this implies 100% CERTAINTY and there’s always a chance that evidence may exist which could REFUTE a theory
step 1 of writing one
- to write the AH & NH for an investigation, you must identify the KEY VARIABLES
IV= manipulated
DV= measured
step 2
- OPERATIONALISE the variables being investigated
- operational values- or operationalising definitions- refer to HOW you will define and measure a specific variable as it’s used in your study
step 3
- decide on a direction for your prediction
a) IF there’s evidence in the literature to SUPPORT a specific effect on the IV on the DV: write a DH
b) IF there are LIMITED/ AMBIGUOUS findings in the lit regarding the effect on the DV: write a ND
2 things are KEY to a good hypothesis
- concise
- clear & simple language
example of a hypothesis
“kids work better on Mon morn than Fri PM”
IV: day
DV: standard of work
Method: give the same group of students both lessons and then measure their immediate recall on the material covered in EACH session
AH: students will significantly recall MORE on the Mon morn
NH: there will be NO significant difference in the amount recalled in each session. Any difference will be due to EITHER:
a) chance
b) CVs
why are we so interested in the NH?
- the AH= more wichtig
- BUT we can NEVER 100% prove the AH, instead we can disprove/ reject the NH
- if we REJECT the NH, it does NOT mean that our AH= correct
- BUT it does provide SUPPORT to it
