inferential statistics: statistical tests: critical + observed values

what is the critical value

the value that must be compared to the observed value to show whether the results are significant

where would you look for the critical value

in the appropriate critical value table- there are different ones for each statistical test

what 3 things to know to find the appropriate critical value (as a whole- even though it depends on each statistical test)

direction of hypothesis- one tailed/directional or two tailed/non-directional. p-value/significance level. degrees of freedom (df) or N- number of cells, number in sample, number of differences

how to find the critical value in a CHI SQUARE TEST

find the degree of freedom. formula is rows-1 x columns-1. determine whether its one tailed or two tailed. compare n to p value in table

how to find the critical value in a SPEARMANS RANK TEST

find n which is the number in the sample. determine whether its one tailed or two tailed. compare n to p value in the table

how to find the critical value in a MANN WHITNEY U TEST

find n which is the number in sample- N1 for IV1 and N2 for IV2. compare in table

how to find the critical value in a SIGN TEST

find n which is the number of differences between variables in the sample. determine whether its one tailed or two tailed. compare n to p value in the table

how to find the critical value in a WILCOXON SIGNED RANKS TEST

determine whether its one tailed or two tailed. find n which is the number of differences between variables in the sample. compare n with p value in the table

what is the observed (calculated value)?

one number based on calculations on all the data collected. hence it can be called the calculated value

what is the observed value for?

by comparing it to the critical value, determines whether results are significant

for a spearmans rho test, what should the relationship between the observed and critical value be for the results to be SIGNIFICANT?

observed value greater than critical value

for a chi square test, what should the relationship between the observed and critical value be for the results to be SIGNIFICANT?

observed value greater than the critical value

for a mann whitney u test, what should the relationship between the observed and critical value be for the results to be SIGNIFICANT?

observed value less than critical value

for a sign test, what should the relationship between the observed and critical value be for the results to be SIGNIFICANT?

observed value less than critical value

for a wilcoxon test, what should the relationship between the observed and critical value be for the results to be SIGNIFICANT?

observed value less than critical value