32.1 Other Issues
32.1.1 Event Studies in marketing
(Skiera, Bayer, and Schöler 2017) What should be the dependent variable in marketing-related event studies?
Based on valuation theory, Shareholder value = the value of the operating business + non-operating asset - debt (Schulze, Skiera, and Wiesel 2012)
- Many marketing events only affect the operating business value, but not non-operating assets and debt
Ignoring the differences in firm-specific leverage effects has dual effects:
inflates the impact of observation pertaining to firms with large debt
deflates those pertaining to firms with large non-operating asset.
It’s recommended that marketing papers should report both CAROB and CARSHV and argue for whichever one more appropriate.
Up until this paper, only two previous event studies control for financial structure: (Gielens et al. 2008) (Chaney, Devinney, and Winer 1991)
Definitions:
Cumulative abnormal percentage return on shareholder value (CARSHV)
- Shareholder value refers to a firm’s market capitalization = share price x # of shares.
Cumulative abnormal percentage return on the value of the operating business (CAROB)
CAROB=CARSHV/leverage effectbefore
Leverage effect = Operating business value / Shareholder value (LE describes how a 1% change in operating business translates into a percentage change in shareholder value).
Value of operating business = shareholder value - non-operating assets + debt
Leverage effect ≠ leverage ratio, where leverage ratio is debt / firm size
debt = long-term + short-term debt; long-term debt
firm size = book value of equity; market cap; total assets; debt + equity
Operating assets are those used by firm in their core business operations (e..g, property, plant, equipment, natural resources, intangible asset)
Non–operating assets (redundant assets), do not play a role in a firm’s operations, but still generate some form of return (e.g., excess cash , marketable securities - commercial papers, market instruments)
Marketing events usually influence the value of a firm’s operating assets (more specifically intangible assets). Then, changes in the value of the operating business can impact shareholder value.
Three rare instances where marketing events can affect non-operating assets and debt
(G. C. Hall, Hutchinson, and Michaelas 2004): excess pre-orderings can influence short-term debt
(Berger, Ofek, and Yermack 1997) Firing CMO increase debt as the manager’s tenure is negatively associated with the firm’s debt
(Bhaduri 2002) production of unique products.
A marketing-related event can either influence
value components of a firm’s value (= firm’s operating business, non-operating assets and its debt)
only the operating business.
Replication of the leverage effect
leverage effect=operating businessshareholder value=(shareholder value - non-operating assets + debt)shareholder value=prccf×csho−ivst+dd1+dltt+pstkprccf×csho
Compustat Data Item
Label | Variable |
---|---|
prcc_f |
Share price |
csho |
Common shares outstanding |
ivst |
short-term investments (Non-operating assets) |
dd1 |
long-term debt due in one year |
dltt |
long-term debt |
pstk |
preferred stock |
Since WRDS no longer maintains the S&P 500 list as of the time of this writing, I can’t replicate the list used in (Skiera, Bayer, and Schöler 2017) paper.
library(tidyverse)
df_leverage_effect <- read.csv("data/leverage_effect.csv.gz") %>%
# get active firms only
filter(costat == "A") %>%
# drop missing values
drop_na() %>%
# create the leverage effect variable
mutate(le = (prcc_f * csho - ivst + dd1 + dltt + pstk)/ (prcc_f * csho)) %>%
# get shareholder value
mutate(shv = prcc_f * csho) %>%
# remove Infinity value for leverage effect (i.e., shareholder value = 0)
filter_all(all_vars(!is.infinite(.))) %>%
# positive values only
filter_all(all_vars(. > 0)) %>%
# get the within coefficient of variation
group_by(gvkey) %>%
mutate(within_var_mean_le = mean(le),
within_var_sd_le = sd(le)) %>%
ungroup()
# get the mean and standard deviation
mean(df_leverage_effect$le)
#> [1] 150.1087
max(df_leverage_effect$le)
#> [1] 183629.6
hist(df_leverage_effect$le)
# coefficient of variation
sd(df_leverage_effect$le) / mean(df_leverage_effect$le) * 100
#> [1] 2749.084
# Within-firm variation (similar to fig 3a)
df_leverage_effect %>%
group_by(gvkey) %>%
slice(1) %>%
ungroup() %>%
dplyr::select(within_var_mean_le, within_var_sd_le) %>%
dplyr::mutate(cv = within_var_sd_le/ within_var_mean_le) %>%
dplyr::select(cv) %>%
pull() %>%
hist()