# load packages
library(tidyverse)
library(tidyquant)
library(moments)
1 Get stock prices and convert to returns
Ra <- c("AMZN", "TGT", "WMT") %>%
tq_get(get = "stock.prices",
from = "2022-01-01") %>%
group_by(symbol) %>%
tq_transmute(select = adjusted,
mutate_fun = periodReturn,
period = "monthly",
col_rename = "Ra")
Ra
## # A tibble: 27 × 3
## # Groups: symbol [3]
## symbol date Ra
## <chr> <date> <dbl>
## 1 AMZN 2022-01-31 -0.122
## 2 AMZN 2022-02-28 0.0267
## 3 AMZN 2022-03-31 0.0614
## 4 AMZN 2022-04-29 -0.238
## 5 AMZN 2022-05-31 -0.0328
## 6 AMZN 2022-06-30 -0.116
## 7 AMZN 2022-07-29 0.271
## 8 AMZN 2022-08-31 -0.0606
## 9 AMZN 2022-09-22 -0.0746
## 10 TGT 2022-01-31 -0.0497
## # … with 17 more rows
2 Get baseline and convert to returns
Rb <- "^IXIC" %>%
tq_get(get = "stock.prices",
from = "2022-01-01") %>%
tq_transmute(select = adjusted,
mutate_fun = periodReturn,
period = "monthly",
col_rename = "Rb")
Rb
## # A tibble: 9 × 2
## date Rb
## <date> <dbl>
## 1 2022-01-31 -0.101
## 2 2022-02-28 -0.0343
## 3 2022-03-31 0.0341
## 4 2022-04-29 -0.133
## 5 2022-05-31 -0.0205
## 6 2022-06-30 -0.0871
## 7 2022-07-29 0.123
## 8 2022-08-31 -0.0464
## 9 2022-09-22 -0.0634
3 Join the two tables
RaRb <- left_join(Ra, Rb, by = c("date" = "date"))
RaRb
## # A tibble: 27 × 4
## # Groups: symbol [3]
## symbol date Ra Rb
## <chr> <date> <dbl> <dbl>
## 1 AMZN 2022-01-31 -0.122 -0.101
## 2 AMZN 2022-02-28 0.0267 -0.0343
## 3 AMZN 2022-03-31 0.0614 0.0341
## 4 AMZN 2022-04-29 -0.238 -0.133
## 5 AMZN 2022-05-31 -0.0328 -0.0205
## 6 AMZN 2022-06-30 -0.116 -0.0871
## 7 AMZN 2022-07-29 0.271 0.123
## 8 AMZN 2022-08-31 -0.0606 -0.0464
## 9 AMZN 2022-09-22 -0.0746 -0.0634
## 10 TGT 2022-01-31 -0.0497 -0.101
## # … with 17 more rows
4 Calculate CAPM
RaRb_capm <- RaRb %>%
tq_performance(Ra = Ra,
Rb = Rb,
performance_fun = table.CAPM)
RaRb_capm
## # A tibble: 3 × 13
## # Groups: symbol [3]
## symbol ActiveP…¹ Alpha Annua…² Beta `Beta-` `Beta+` Corre…³ Corre…⁴ Infor…⁵
## <chr> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
## 1 AMZN -0.0125 0.0343 0.499 1.82 1.95 2.34 0.978 0 -0.0517
## 2 TGT -0.035 -0.0137 -0.153 0.594 -1.99 1.06 0.352 0.353 -0.0802
## 3 WMT 0.292 0.011 0.140 0.436 -0.872 -0.223 0.43 0.248 1.01
## # … with 3 more variables: `R-squared` <dbl>, TrackingError <dbl>,
## # TreynorRatio <dbl>, and abbreviated variable names ¹ActivePremium,
## # ²AnnualizedAlpha, ³Correlation, ⁴`Correlationp-value`, ⁵InformationRatio
Which stock has a positively skewed distribution of returns?
RaRb_skew <- RaRb %>%
tq_performance(Ra = Ra,
# Rb = Rb,
performance_fun = skewness)
RaRb_skew
## # A tibble: 3 × 2
## # Groups: symbol [3]
## symbol skewness.1
## <chr> <dbl>
## 1 AMZN 0.835
## 2 TGT -0.468
## 3 WMT -0.411