library(tidyverse)
library(tidyquant) # for financial analysis
library(broom) # for tidy model results
library(umap) # for dimension reduction
library(plotly) # for interactive visualization
# Get info on companies listed in S&P500
sp500_index_tbl <- tq_index("SP500")
# Get individual stocks from S&P500
sp500_symbols <- sp500_index_tbl %>% distinct(symbol) %>% pull()
# Get stock prices of the companies
sp500_prices_tbl <- tq_get(sp500_symbols, from = "2020-04-01")
write.csv(sp500_index_tbl, "../00_data/sp500_index_tbl.csv")
write.csv(sp500_prices_tbl, "../00_data/sp500_prices_tbl.csv")
Import data
sp500_index_tbl <- read_csv("../00_data/sp500_index_tbl.csv")
sp500_prices_tbl <- read_csv("../00_data/sp500_prices_tbl.csv")
sp500_index_tbl %>% glimpse()
## Rows: 504
## Columns: 9
## $ ...1 <dbl> 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, …
## $ symbol <chr> "AAPL", "MSFT", "NVDA", "AMZN", "META", "BRK-B", "GOOGL…
## $ company <chr> "APPLE INC", "MICROSOFT CORP", "NVIDIA CORP", "AMAZON.C…
## $ identifier <chr> "037833100", "594918104", "67066G104", "023135106", "30…
## $ sedol <chr> "2046251", "2588173", "2379504", "2000019", "B7TL820", …
## $ weight <dbl> 0.063852496, 0.063282113, 0.058805166, 0.038154398, 0.0…
## $ sector <chr> "-", "-", "-", "-", "-", "-", "-", "-", "-", "-", "-", …
## $ shares_held <dbl> 185532921, 91814848, 302468387, 116491471, 27046746, 22…
## $ local_currency <chr> "USD", "USD", "USD", "USD", "USD", "USD", "USD", "USD",…
sp500_prices_tbl %>% glimpse()
## Rows: 629,218
## Columns: 9
## $ ...1 <dbl> 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18…
## $ symbol <chr> "AAPL", "AAPL", "AAPL", "AAPL", "AAPL", "AAPL", "AAPL", "AAPL…
## $ date <date> 2020-04-01, 2020-04-02, 2020-04-03, 2020-04-06, 2020-04-07, …
## $ open <dbl> 61.6250, 60.0850, 60.7000, 62.7250, 67.7000, 65.6850, 67.1750…
## $ high <dbl> 62.1800, 61.2875, 61.4250, 65.7775, 67.9250, 66.8425, 67.5175…
## $ low <dbl> 59.7825, 59.2250, 59.7425, 62.3450, 64.7500, 65.3075, 66.1750…
## $ close <dbl> 60.2275, 61.2325, 60.3525, 65.6175, 64.8575, 66.5175, 66.9975…
## $ volume <dbl> 176218400, 165934000, 129880000, 201820400, 202887200, 168895…
## $ adjusted <dbl> 58.46381, 59.43937, 58.58514, 63.69596, 62.95821, 64.56960, 6…
Which stock prices behave similarly?
Our main objective is to identify stocks that exhibit similar price behaviors over time. By doing so, we aim to gain insights into the relationships between different companies, uncovering potential competitors and sector affiliations.
Why It Matters Understanding which companies are related is crucial for various reasons:
Assignment Details Your task is to analyze the historical price data of various stocks and determine which stocks behave similarly. We will employ clustering techniques to accomplish this task effectively.
To compare data effectively, it must be standardized or normalized. Why? Because comparing values (like stock prices) of vastly different magnitudes is impractical. So, we’ll standardize by converting from adjusted stock price (in dollars) to daily returns (as percent change from the previous day). Here’s the formula:
\[ return_{daily} = \frac{price_{i}-price_{i-1}}{price_{i-1}} \]
sp500_prices_tbl %>% glimpse()
## Rows: 629,218
## Columns: 9
## $ ...1 <dbl> 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18…
## $ symbol <chr> "AAPL", "AAPL", "AAPL", "AAPL", "AAPL", "AAPL", "AAPL", "AAPL…
## $ date <date> 2020-04-01, 2020-04-02, 2020-04-03, 2020-04-06, 2020-04-07, …
## $ open <dbl> 61.6250, 60.0850, 60.7000, 62.7250, 67.7000, 65.6850, 67.1750…
## $ high <dbl> 62.1800, 61.2875, 61.4250, 65.7775, 67.9250, 66.8425, 67.5175…
## $ low <dbl> 59.7825, 59.2250, 59.7425, 62.3450, 64.7500, 65.3075, 66.1750…
## $ close <dbl> 60.2275, 61.2325, 60.3525, 65.6175, 64.8575, 66.5175, 66.9975…
## $ volume <dbl> 176218400, 165934000, 129880000, 201820400, 202887200, 168895…
## $ adjusted <dbl> 58.46381, 59.43937, 58.58514, 63.69596, 62.95821, 64.56960, 6…
# Apply your data transformation skills!
sp_500_daily_returns_tbl <- sp500_prices_tbl %>%
select(symbol, date, adjusted) %>%
filter(date >= ymd("2018-01-01")) %>%
group_by(symbol) %>%
mutate(lag_1 = lag(adjusted)) %>%
ungroup() %>%
filter(!is.na(lag_1)) %>%
mutate(diff = adjusted - lag_1) %>%
mutate(pct_return = diff / lag_1) %>%
select(symbol, date, pct_return)
sp_500_daily_returns_tbl
## # A tibble: 628,715 × 3
## symbol date pct_return
## <chr> <date> <dbl>
## 1 AAPL 2020-04-02 0.0167
## 2 AAPL 2020-04-03 -0.0144
## 3 AAPL 2020-04-06 0.0872
## 4 AAPL 2020-04-07 -0.0116
## 5 AAPL 2020-04-08 0.0256
## 6 AAPL 2020-04-09 0.00722
## 7 AAPL 2020-04-13 0.0196
## 8 AAPL 2020-04-14 0.0505
## 9 AAPL 2020-04-15 -0.00913
## 10 AAPL 2020-04-16 0.00795
## # ℹ 628,705 more rows
We’ll convert the daily returns (percentage change from one day to the next) to object-characteristics format, also known as the user-item format. Users are identified by the symbol (company), and items are represented by the pct_return at each date.
stock_date_matrix_tbl <- sp_500_daily_returns_tbl %>%
spread(key = date, value = pct_return, fill = 0)
stock_date_matrix_tbl
## # A tibble: 503 × 1,264
## symbol `2020-04-02` `2020-04-03` `2020-04-06` `2020-04-07` `2020-04-08`
## <chr> <dbl> <dbl> <dbl> <dbl> <dbl>
## 1 A 0.0489 -0.0259 0.0559 -0.00444 0.0359
## 2 AAPL 0.0167 -0.0144 0.0872 -0.0116 0.0256
## 3 ABBV 0.0233 -0.0234 0.0322 -0.00449 0.0420
## 4 ABNB 0 0 0 0 0
## 5 ABT 0.0375 0.000126 0.0413 -0.00967 0.0369
## 6 ACGL 0.0115 -0.0650 0.0983 0.0314 0.0291
## 7 ACN 0.0103 -0.0264 0.0914 -0.0116 0.0464
## 8 ADBE 0.00913 -0.0341 0.0869 -0.0320 0.0267
## 9 ADI 0.0429 -0.0130 0.107 0.00470 0.0535
## 10 ADM 0.0136 0.00932 0.0326 0.00559 0.0139
## # ℹ 493 more rows
## # ℹ 1,258 more variables: `2020-04-09` <dbl>, `2020-04-13` <dbl>,
## # `2020-04-14` <dbl>, `2020-04-15` <dbl>, `2020-04-16` <dbl>,
## # `2020-04-17` <dbl>, `2020-04-20` <dbl>, `2020-04-21` <dbl>,
## # `2020-04-22` <dbl>, `2020-04-23` <dbl>, `2020-04-24` <dbl>,
## # `2020-04-27` <dbl>, `2020-04-28` <dbl>, `2020-04-29` <dbl>,
## # `2020-04-30` <dbl>, `2020-05-01` <dbl>, `2020-05-04` <dbl>, …
stock_cluster <- kmeans(stock_date_matrix_tbl %>% select(-symbol), centers = 3, nstart = 20)
summary(stock_cluster)
## Length Class Mode
## cluster 503 -none- numeric
## centers 3789 -none- numeric
## totss 1 -none- numeric
## withinss 3 -none- numeric
## tot.withinss 1 -none- numeric
## betweenss 1 -none- numeric
## size 3 -none- numeric
## iter 1 -none- numeric
## ifault 1 -none- numeric
tidy(stock_cluster)
## # A tibble: 3 × 1,266
## `2020-04-02` `2020-04-03` `2020-04-06` `2020-04-07` `2020-04-08` `2020-04-09`
## <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
## 1 0.0174 -0.0136 0.0648 0.00118 0.0386 0.0226
## 2 0.0114 -0.0178 0.0916 -0.00234 0.0357 0.00833
## 3 0.00694 -0.0185 0.102 0.0307 0.0603 0.0379
## # ℹ 1,260 more variables: `2020-04-13` <dbl>, `2020-04-14` <dbl>,
## # `2020-04-15` <dbl>, `2020-04-16` <dbl>, `2020-04-17` <dbl>,
## # `2020-04-20` <dbl>, `2020-04-21` <dbl>, `2020-04-22` <dbl>,
## # `2020-04-23` <dbl>, `2020-04-24` <dbl>, `2020-04-27` <dbl>,
## # `2020-04-28` <dbl>, `2020-04-29` <dbl>, `2020-04-30` <dbl>,
## # `2020-05-01` <dbl>, `2020-05-04` <dbl>, `2020-05-05` <dbl>,
## # `2020-05-06` <dbl>, `2020-05-07` <dbl>, `2020-05-08` <dbl>, …
glance(stock_cluster)
## # A tibble: 1 × 4
## totss tot.withinss betweenss iter
## <dbl> <dbl> <dbl> <int>
## 1 206. 178. 28.0 3
augment(stock_cluster, stock_date_matrix_tbl) %>%
ggplot(aes("2020-04-02","2020-08-20", color = .cluster)) +
geom_point()
kclusters <- tibble(k = 1:9) %>%
mutate(kclust = map(.x = k, .f = ~ kmeans(stock_date_matrix_tbl %>% select(-symbol), centers = .x, nstart = 20)),
glanced = map(.x = kclust, .f = glance))
kclusters %>%
unnest(glanced) %>%
ggplot(aes(k, tot.withinss)) +
geom_point() +
geom_line()
stock_final_cluster <- kmeans(stock_date_matrix_tbl %>% select(-symbol), centers = 5, nstart = 20)
augment(stock_final_cluster, stock_date_matrix_tbl) %>%
ggplot(aes(`2020-04-02`,`2020-08-20`, color = .cluster)) +
geom_point()
stock_umap_results <- stock_date_matrix_tbl %>%
select(-symbol) %>%
umap()
umap_results_tbl <- stock_umap_results$layout %>%
as.tibble() %>%
bind_cols(stock_date_matrix_tbl %>% select(symbol))
umap_results_tbl
## # A tibble: 503 × 3
## V1 V2 symbol
## <dbl> <dbl> <chr>
## 1 2.34 1.51 A
## 2 3.00 0.0493 AAPL
## 3 0.0527 2.29 ABBV
## 4 2.53 -0.862 ABNB
## 5 1.01 1.79 ABT
## 6 -1.23 -0.939 ACGL
## 7 1.79 0.00816 ACN
## 8 3.18 -0.167 ADBE
## 9 3.02 -1.73 ADI
## 10 -1.17 -0.545 ADM
## # ℹ 493 more rows
stock_kmeans_umap_tbl <- stock_final_cluster %>%
augment(stock_date_matrix_tbl) %>%
select(symbol, .cluster) %>%
# Add Umap Results
left_join(umap_results_tbl) %>%
left_join(sp500_index_tbl %>% select(symbol, company, sector), by = "symbol")
stock_kmeans_umap_tbl
## # A tibble: 503 × 6
## symbol .cluster V1 V2 company sector
## <chr> <fct> <dbl> <dbl> <chr> <chr>
## 1 A 1 2.34 1.51 AGILENT TECHNOLOGIES INC -
## 2 AAPL 2 3.00 0.0493 APPLE INC -
## 3 ABBV 5 0.0527 2.29 ABBVIE INC -
## 4 ABNB 2 2.53 -0.862 AIRBNB INC CLASS A -
## 5 ABT 5 1.01 1.79 ABBOTT LABORATORIES -
## 6 ACGL 1 -1.23 -0.939 ARCH CAPITAL GROUP LTD -
## 7 ACN 1 1.79 0.00816 ACCENTURE PLC CL A -
## 8 ADBE 2 3.18 -0.167 ADOBE INC -
## 9 ADI 2 3.02 -1.73 ANALOG DEVICES INC -
## 10 ADM 5 -1.17 -0.545 ARCHER DANIELS MIDLAND CO -
## # ℹ 493 more rows
graph <- stock_kmeans_umap_tbl %>%
# Create text label
mutate(text_label = str_glue("Ticker: {symbol}
Cluster: {.cluster}
Company: {company}
Sector: {sector}")) %>%
# Plot
ggplot(aes(V1, V2, color = .cluster, text = text_label)) +
geom_point()
graph %>% ggplotly(tooltip = "text")