What is a hypothesis? • Give an example of a hypothesis, based on a study you know about.
Hypothesis • A prediction about the outcome of a piece of research • An experimental hypothesis must predict the effect of the IV on the DV
Experimental hypotheses • A researcher dressed in uniform will be obeyed more often than a researcher dressed in civilian clothes. • Words that PPs have processed semantically are more likely to be recognised than words that they have processed structurally.
Experimental hypotheses • Suggest experimental hypotheses for the following studies: • Jenkins & Dallenbach (1924) • Godden & Baddeley (1975)
Experimental hypotheses • Directional hypotheses predict the direction in which the results are expected to run • Non-directional hypotheses predict an effect of the IV on the DV, but not a direction
Jenkins & Dallenbach (1924) • PPs who learn the word list before sleeping will recall more words than PPs who learn the list after waking. • There will be a difference in the number of words recalled between PPs who learn the list before sleeping and those who learn it after waking.
Testing hypotheses • Hypotheses predict results of experiments • They must be tested against the data and either accepted or rejected
Summarising data • Before we can assess whether the data support or challenge the experimental hypothesis we must prepare a statistical summary • Any set of data can be summarised to two figures: • Central tendency • Dispersion
Central tendency Tells you a typical value from a set of data Mode Median Mean Dispersion Tells you how close to the central tendency the values in the set are Range Standard deviation Summarising data
Concept maps vs. notes • IV: revision strategy used • DV: score on a recall test (max. 20) • H1: PPs using concept maps will recall more than PPs using notes.
Organised vs. disorganised • IV: info in categories or randomised • DV: score on a recall test (max. 20) • H1: there will be a difference in recall between PPs who are give organised info and PPs who are given disorganised info.
Review • Identify… • One thing you already knew • One fact you learned • One skill you developed • Something that was difficult and will need more work.