statistical tests

P value is important to accept or reject null hypothesis

• True

• False

which level of significance (alpha) is common? choose Three answers

• 0.1

• 0.5

• 0.01

• 0.05

• 0.00001

What is the best test for this situation?

the relation between gender and shoes colors

choose all possible answers

• Fischer's test

• Chi-square test of independency

• ANOVA

• t- test

• Pearson's correlation

number of defects were recorded for two machines. To test whether the expensive machine has less defects than the cheap one, choose all possible answers

• One tail test

• Test of normality of each group

• T test may be used

• Paired T test may be used

• Two tail test

To test if there is a linear relation between the years of experience and salary for each employee, Please choose right and properly arranged steps

A. Pearson's test

B. Normality test

C. Paired T test

D. Test of homogeneity

• B,D,A

• B,D,C

• A

• C

To test whether the flipper_length is significanly different between Adellie, Chinstrap and Gentoo,

Choose all the possible answer

• Kruskal's Walis test may be used

• ANOVA test may be used

• Mann Whitney's test may be used

• WillCoxon's test may be used

if you explore your data first by visualization, what is the best to do?

Choose all the possible answers

• Test of normality and if data normal make ANOVA

• If Anova significant make multiple comparison tests

• Test of normality and if data is not normal use Kruskal's Walis test

• Test of normality and if data is not normal try to make transformation

• Non of the above

X is categorical (5 categories) an y is numerical

to check if y is different among x categories this steps is done

test of normality: p value =0.5

choose the most accurate answer to continue the analysis

• Kruskal Wallis test then Mann Whitney's test to compare

• ANOVA Then multiple comparison test

• Homogenity test then ANOVA then multiple comparison test

• ANOVA then homogenity test then multiple comparison test

for homogeneity test among three groups

the result was p value = 0.01

then

• Standard deviation is different between groups

• Equal variance not assumed

• Reject null hypothesis

• All of the above