source('utils.R')
source('http://waxworksmath.com/Authors/A_F/Devore/Code/Chapter15/kruskal_wallis_test.R')


# Section 4; Question 1:
#
source('../Chapter8/chap_8_sect_2_question_7_data.R')
res = kruskal_wallis_test( DF, 'group_number', 'iq_change', check_sample_sizes=FALSE, debugging=FALSE )
print( sprintf( 'B= %.3f; B_crit= %.3f; p_value= %.6f', res$K, res$k_crit, res$p_value ) )


# Section 4; Question 2:
#
source('../Chapter9/chap_9_sect_5_question_2_data.R')
res = kruskal_wallis_test( DF, 'With_Domes', 'Percent_Time', check_sample_sizes=FALSE, debugging=FALSE )
print( sprintf( 'B= %.3f; B_crit= %.3f; p_value= %.6f', res$K, res$k_crit, res$p_value ) )


# Section 4; Question 3:
#
source('../Chapter9/chap_9_sect_2_question_8_data.R')
res = kruskal_wallis_test( DF, 'Sex', 'Halflife' )
print( sprintf( 'B= %.3f; B_crit= %.3f; p_value= %.6f', res$K, res$k_crit, res$p_value ) )


# Section 4; Question 4:
#
source('../Chapter9/case_study_9_2_1_data.R')
res = kruskal_wallis_test( DF, 'author', 'prop' )
print( sprintf( 'B= %.3f; B_crit= %.3f; p_value= %.6f', res$K, res$k_crit, res$p_value ) )


# Section 4; Question 5:
#
source('../Chapter12/case_study_12_2_1_data.R')
res = kruskal_wallis_test( DF, 'smoker_type', 'value' )
print( sprintf( 'B= %.3f; B_crit= %.3f; p_value= %.6f', res$K, res$k_crit, res$p_value ) )


# Section 4; Question 6:
#
source('chap_14_sect_4_question_6_data.R')
library(reshape2)
DF_melt = melt(DF, id.vars=c(), variable.name='Plant', value.name='Value')

# Part (a):
#
res = kruskal_wallis_test( DF_melt, 'Plant', 'Value' )
print( sprintf( 'B= %.3f; B_crit= %.3f; p_value= %.6f', res$K, res$k_crit, res$p_value ) )

# Part (b):
#
DF$Plant = as.factor( DF$Plant )
am = aov( Value ~ Plant, data=DF_melt )
summary(am)

# Part (c):
#
row_of_interest = DF_melt$Value == 2246
DF_melt[ row_of_interest, 'Value'] = 1500
res = kruskal_wallis_test( DF_melt, 'Plant', 'Value' )
print( sprintf( '2246 => 1500: B= %.3f; B_crit= %.3f; p_value= %.6f', res$K, res$k_crit, res$p_value ) )

# Part (d):
#
am = aov( Value ~ Plant, data=DF_melt )
summary(am)


# Section 4; Question 7:
#
source('chap_14_sect_4_question_7_data.R')
library(reshape2)
DF_melt = melt(DF, id.vars=c(), variable.name='Type', value.name='Value')
res = kruskal_wallis_test( DF_melt, 'Type', 'Value' )
print( sprintf( 'B= %.3f; B_crit= %.3f; p_value= %.6f', res$K, res$k_crit, res$p_value ) )