research methods ; probability + significance 0.0 / 5 ? PsychologyResearch methods and techniquesA2/A-levelAQA Created by: ilovetheofficeCreated on: 13-05-18 14:25 PROBABILITY AND SIGNIFICANCE GD 1 of 34 - the null hypothesis dfgdg 2 of 34 what two things may hypotheses be? directional / non-directional 3 of 34 what may these two types of hypotheses also be referred to as? alternative hypothesis 4 of 34 why? alternative to null hypothesis 5 of 34 what does null hypothesis state? there is no difference between conditions 6 of 34 what determines which hypothesis is true + whether we accept or reject null? stats test 7 of 34 - levels of significance and probability dfgd 8 of 34 stats tests don't work on certainty but? probability 9 of 34 all stats tests emply a significance level which is? pt at which researcher can claim to have discovered significant difference / correlation within data 10 of 34 in other words pt @ which researcher cna do what? reject null + accept alternative 11 of 34 what is the usual level of significance? 5% / 0.05 / p < 0.05 12 of 34 what does this mean? probability that observed effect occured by chance is equal to / less than 5% 13 of 34 in effect when researcher claims to have found difference / correlation there's still 5% chance it was a fluke 14 of 34 why can psychologists never b 100% certain about particular result? they haven't tested all members of population under all possible circumstances 15 of 34 for this reason conventional probability level is? 5% 16 of 34 USE OF STATS TABLES DFGDF 17 of 34 - critical value dfdf 18 of 34 what is the calculated value? number you get from the stats tet 19 of 34 to check for stat significance what do you have to do with this? compare to critical value 20 of 34 what is the critical valy? number that tells us whether or not we can reject the null and accept alternative 21 of 34 - lower levels of significance dfgd 22 of 34 occasionally more stringent significance level used like 0.01 why? may be human cost like drug trial or 'one-offs' thay couldnt be repeated 23 of 34 in all research if there's a large difference between calculated / critical what will happen? researcher will check more stringent levels 24 of 34 and the lwoer the p value? the more statistically significant 25 of 34 TYPE I AND TYPE II ERRORS DFG 26 of 34 what is a type i error? when null rejected and alternative accepted when should be other way round 27 of 34 what kind of error is this also referred to as? optomistic error / false positive 28 of 34 why? researcher claims to have fuond significant diff / correlation when one doesn't exist 29 of 34 what is a typeii error? null accepted but should have been alternative bc that was true 30 of 34 also known as? pessimistic error / false negative 31 of 34 more likely to make type i error when significance level is? too lenient like 10% 32 of 34 and type ii more likely with significance? too stringent like 1% 33 of 34 so why did we land @ 5% level? best balances risk of type i / type ii error 34 of 34
Comments
No comments have yet been made