# Load package
library(tidyverse)
library(tidyquant)
1 Get stock prices and convert to returns
Ra <- c("UA", "NKE", "LULU") %>%
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: 123 × 3
## # Groups: symbol [3]
## symbol date Ra
## <chr> <date> <dbl>
## 1 UA 2022-01-31 -0.115
## 2 UA 2022-02-28 -0.0225
## 3 UA 2022-03-31 -0.00448
## 4 UA 2022-04-29 -0.0880
## 5 UA 2022-05-31 -0.316
## 6 UA 2022-06-30 -0.219
## 7 UA 2022-07-29 0.0897
## 8 UA 2022-08-31 -0.0811
## 9 UA 2022-09-30 -0.215
## 10 UA 2022-10-31 0.101
## # ℹ 113 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: 41 × 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 2022-09-30 -0.105
## 10 2022-10-31 0.0390
## # ℹ 31 more rows
3 Join the two tables
RaRb <- left_join(Ra, Rb, by = c("date" = "date"))
RaRb
## # A tibble: 123 × 4
## # Groups: symbol [3]
## symbol date Ra Rb
## <chr> <date> <dbl> <dbl>
## 1 UA 2022-01-31 -0.115 -0.101
## 2 UA 2022-02-28 -0.0225 -0.0343
## 3 UA 2022-03-31 -0.00448 0.0341
## 4 UA 2022-04-29 -0.0880 -0.133
## 5 UA 2022-05-31 -0.316 -0.0205
## 6 UA 2022-06-30 -0.219 -0.0871
## 7 UA 2022-07-29 0.0897 0.123
## 8 UA 2022-08-31 -0.0811 -0.0464
## 9 UA 2022-09-30 -0.215 -0.105
## 10 UA 2022-10-31 0.101 0.0390
## # ℹ 113 more rows
4 Calculate CAPM
RaRb_capm <- RaRb %>%
tq_performance(Ra = Ra,
Rb = Rb,
performance_fun = table.CAPM)
RaRb_capm
## # A tibble: 3 × 18
## # Groups: symbol [3]
## symbol ActivePremium Alpha AlphaRobust AnnualizedAlpha Beta `Beta-`
## <chr> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
## 1 UA -0.318 -0.0243 -0.0277 -0.256 1.29 0.272
## 2 NKE -0.296 -0.0232 -0.0168 -0.245 0.761 0.692
## 3 LULU -0.113 -0.0047 -0.0042 -0.055 0.968 0.700
## # ℹ 11 more variables: `Beta-Robust` <dbl>, `Beta+` <dbl>, `Beta+Robust` <dbl>,
## # BetaRobust <dbl>, Correlation <dbl>, `Correlationp-value` <dbl>,
## # InformationRatio <dbl>, `R-squared` <dbl>, `R-squaredRobust` <dbl>,
## # TrackingError <dbl>, TreynorRatio <dbl>