probability and significance- research methods

Question 1

the null hypothesis

Answer 1

direction or non directional hypothesis
null hypothesis states there is no difference betyween conditions
statistical test determines which hypothesis is true and whether we accept or reject the null hypothesis

Question 2

levels of significance and probability

Answer 2

employ significance level the point at which the researcher can claim to have discoverd large enough difference or correlation within the data to claim and effect has been found
point at which researcher can reject null hypothesis and acept alternative hypothesis
p less than or equal to 0.05
probability observed effect occurred when there is no effect in the population equal to or less than 5%
even when researcher claims to have found significant difference or correlation there is still up to 5% chance that it isnt true for target population

Question 3

calculated and critical values

Answer 3

result is calculated value
calculated value must be compared with critical value- number that tells us whether or not we can reject the null hypothesis and accept alternative hypothesis

Question 4

using tables of critical values

Answer 4

one tailed or two tailed- one tailed if hypothesis directional and two tailed for non directional, probability levels double when two tailed tests used as more conservative prediction
number of pps in the study-appears as n number or degrees of freedom
level of significance- 0.05

Question 5

type one and type two errors

Answer 5

type 1- null hypothesis rejected and laternative is accepted when it should have been the other way round because null is true
type two error- null accepted but should have been alternative hypothesis because this is true
more likely for type 1 if significance level too high and type 2 if too low