output

t_test_pneg = 0
t_test_pneu = 0
t_test_nneu = 0
ans =

   0.4820   0.5271   0.5012

t_test_polarity_pneg = 0.9589
t_test_polarity_pneu = 0
t_test_polarity_nneu = 0
ans =

   0.082398   0.082379   0.835217

tests.m

clear all
clc
close all

sentiment = csvread('covid-sentiment.csv');
data = sentiment';

compound = data(1, :, :, :);
compound = compound';


# positive ranked tweets
alpha = 0.05;
positive = compound > alpha;
num_positive = sum(positive);

# negative ranked tweets
negative = compound < -alpha;
num_negative = sum(negative);

# neutral
neutral = (compound <= alpha) & (compound >= -alpha);
num_neutral = sum(neutral);

function output = ilerp(a, b, t)
  output = (t - a) / (b - a);
end


# get data
positive_vals = compound(positive);
negative_vals = abs(compound(negative));
neutral_vals  = compound(neutral);

normalised_pos = ilerp(0.05, 1, positive_vals);
normalised_neg = ilerp(0.05, 1, negative_vals);
normalised_neu = ilerp(-0.05, 0.05, neutral_vals);


# get avgs
positive_avg = mean(positive_vals);
negative_avg = mean(negative_vals);
neutral_avg = mean(neutral_vals);

# t-test
# [h, t_test_pneg] = ttest2(positive_vals, negative_vals, 'Vartype','unequal')
# [h, t_test_pneu] = ttest2(positive_vals, neutral_vals, 'Vartype','unequal')
# [h, t_test_nneu] = ttest2(negative_vals, neutral_vals, 'Vartype','unequal')

[~, t_test_pneg] = ttest2(normalised_pos, normalised_neg, 'Vartype','unequal')
[~, t_test_pneu] = ttest2(normalised_pos, normalised_neu, 'Vartype','unequal')
[~, t_test_nneu] = ttest2(normalised_neg, normalised_neu, 'Vartype','unequal')

[mean(normalised_pos), mean(normalised_neg), mean(normalised_neu)]



negative_sentiment = sentiment(:, 2);
neutral_sentiment  = sentiment(:, 3);
positive_sentiment = sentiment(:, 4);

[~, t_test_polarity_pneg] = ttest2(positive_sentiment, negative_sentiment)
[~, t_test_polarity_pneu] = ttest2(positive_sentiment, neutral_sentiment)
[~, t_test_polarity_nneu] = ttest2(negative_sentiment, neutral_sentiment)

[mean(positive_sentiment), mean(negative_sentiment), mean(neutral_sentiment)]