hmax_familiarvsunfamiliar-id.Rmd

---
title: "Decoding of Familiarity with HMAX C1, C2 features"
output: html_notebook
---

```{r}
require(plyr)
require(tidyverse)
```
```{r}
# load dataset
df <- read_csv('../../results/hmax_famvsunf-id/hmax_famvsunfam-id_c1c2_perm.csv')
df
```
```{r}
# bootstrap n_bs permutation for each subject
n_bs <- 10000
# set seed for reproducibility
set.seed(444)
df_null <-
df %>%
    group_by(subject) %>%
    sample_n(n_bs, replace=T) %>%
    mutate(i_bs=1:n_bs) %>%
    group_by(i_bs) %>%
    summarise(acc_c1=mean(acc_c1), acc_c2=mean(acc_c2)) 

# get original values
df_orig <-
    df %>%
    filter(permutation == 'perm00') %>%
    summarise(acc_c1=mean(acc_c1), acc_c2=mean(acc_c2)) 
```
Now plot null distributions for C1
```{r}
# empirical p-value
pval_c1 <- 
    1 - (sum(df_null$acc_c1 <= df_orig$acc_c1) + 1)/(n_bs + 1)
pval_c2 <- 
    1 - (sum(df_null$acc_c2 <= df_orig$acc_c2) + 1)/(n_bs + 1)

pval <-
  data.frame(pval=c(pval_c1, pval_c2),
             layer=c('acc_c1', 'acc_c2'))

# gather dataframe so we can plot everything together
df_orig_g <- gather(df_orig, key='layer', value='acc')
df_null_g <- gather(df_null, key='layer', value='acc', -i_bs)
```

```{r, fig.height=5, fig.width=8}
df_null_g$layer_lbl <- mapvalues(df_null_g$layer, c('acc_c1', 'acc_c2'), c('Layer C1', 'Layer C2'))
df_orig_g$layer_lbl <- mapvalues(df_orig_g$layer, c('acc_c1', 'acc_c2'), c('Layer C1', 'Layer C2'))
pval$layer_lbl <- mapvalues(pval$layer, c('acc_c1', 'acc_c2'), c('Layer C1', 'Layer C2'))

ggplot(df_null_g) + 
  geom_histogram(aes(acc), bins=100, fill='lightgray') +
  geom_vline(xintercept=.5, linetype='dashed', color='black') +
  geom_vline(data=df_orig_g, aes(xintercept=acc), linetype='dashed', color='blue') +
  theme_bw(base_size=12) +
  labs(x='Classifier Accuracy', y='Histogram Count') +
  geom_text(data=df_orig_g, x=.45, y=300, 
             aes(label=paste('M =', round(acc, 2))),
            hjust='left') +
  geom_text(data=pval, x=.45, y=280, 
             aes(label=paste('p =', round(pval, 2))),
            hjust='left') +
  facet_wrap(~layer_lbl)

ggsave('hmax_familiarvsunfamiliar-id_decoding.png', width=8, height=5)
```