Movie Ratings Summary
Astrid Cardenas-Valles
2026-09-14
Introduction
This R Markdown document will read a movie rating dataset and calculate basic summary statistic for the movie ratings.
Read the dataset
# Load the readr package
library(readr)## Warning: package 'readr' was built under R version 4.4.3# Read the movie_ratings.csv file
movies <- read_csv("movie_ratings.csv")## Rows: 520 Columns: 13
## ── Column specification ────────────────────────────────────────────────────────
## Delimiter: ","
## chr (6): Const, Title, URL, Title Type, Genres, Directors
## dbl (5): Your Rating, IMDb Rating, Runtime (mins), Year, Num Votes
## date (2): Date Rated, Release Date
##
## ℹ Use `spec()` to retrieve the full column specification for this data.
## ℹ Specify the column types or set `show_col_types = FALSE` to quiet this message.# Display the dataset
movies## # A tibble: 520 × 13
## Const `Your Rating` `Date Rated` Title URL `Title Type` `IMDb Rating`
## <chr> <dbl> <date> <chr> <chr> <chr> <dbl>
## 1 tt10062338 7 2022-08-12 Earwig http… movie 5.4
## 2 tt10095582 6 2022-01-22 The T… http… movie 7.1
## 3 tt10095856 10 2019-04-17 Ramms… http… musicVideo 9.2
## 4 tt1014759 5 2018-08-03 Alice… http… movie 6.4
## 5 tt1017460 6 2018-07-30 Splice http… movie 5.8
## 6 tt1020530 6 2018-08-03 Eden … http… movie 6.7
## 7 tt0102510 8 2022-11-10 The N… http… movie 6.9
## 8 tt10272534 10 2020-11-24 Lvx Æ… http… movie 6.3
## 9 tt1028532 7 2018-07-30 Hachi… http… movie 8.1
## 10 tt1032846 7 2018-08-06 4 lun… http… movie 7.9
## # ℹ 510 more rows
## # ℹ 6 more variables: `Runtime (mins)` <dbl>, Year <dbl>, Genres <chr>,
## # `Num Votes` <dbl>, `Release Date` <date>, Directors <chr># Check the number of rows and columns
dim(movies)## [1] 520 13# Display names of the variables
names(movies)## [1] "Const" "Your Rating" "Date Rated" "Title"
## [5] "URL" "Title Type" "IMDb Rating" "Runtime (mins)"
## [9] "Year" "Genres" "Num Votes" "Release Date"
## [13] "Directors"# Generate summary statistics for dataset
summary(movies)## Const Your Rating Date Rated Title
## Length:520 Min. : 1.00 Min. :2018-07-25 Length:520
## Class :character 1st Qu.: 6.00 1st Qu.:2018-08-03 Class :character
## Mode :character Median : 7.00 Median :2018-08-18 Mode :character
## Mean : 6.79 Mean :2019-10-19
## 3rd Qu.: 8.00 3rd Qu.:2021-04-17
## Max. :10.00 Max. :2023-01-17
##
## URL Title Type IMDb Rating Runtime (mins)
## Length:520 Length:520 Min. :2.500 Min. : 4.0
## Class :character Class :character 1st Qu.:5.700 1st Qu.: 89.0
## Mode :character Mode :character Median :6.500 Median :100.0
## Mean :6.461 Mean :103.3
## 3rd Qu.:7.300 3rd Qu.:117.0
## Max. :9.200 Max. :201.0
## NA's :3
## Year Genres Num Votes Release Date
## Min. :1948 Length:520 Min. : 32 Min. :1948-08-23
## 1st Qu.:2008 Class :character 1st Qu.: 5054 1st Qu.:2008-07-01
## Median :2014 Mode :character Median : 73810 Median :2013-12-17
## Mean :2011 Mean : 216092 Mean :2011-09-17
## 3rd Qu.:2018 3rd Qu.: 261012 3rd Qu.:2018-04-22
## Max. :2022 Max. :2660102 Max. :2022-10-25
##
## Directors
## Length:520
## Class :character
## Mode :character
##
##
##
## # Calculate the mean IMDb rating
mean(movies$`IMDb Rating`, na.rm = TRUE)## [1] 6.461346# Calculate the median IMDb rating
median(movies$`IMDb Rating`, na.rm = TRUE)## [1] 6.5# Find the minimum IMDb rating
min(movies$`IMDb Rating`, na.rm = TRUE)## [1] 2.5# Find the maximum IMDb rating
max(movies$`IMDb Rating`, na.rm = TRUE)## [1] 9.2# Calculate the standard deviation of IMDb ratings
sd(movies$`IMDb Rating`, na.rm = TRUE)## [1] 1.197407Distribution of IMDb Ratings
# Create a histogram showing the distribution of IMDb ratings
hist(movies$`IMDb Rating`, main = "Distribution of IMDb Ratings", xlab = "IMDb Rating")
Figure 1.Distribution of IMDb Ratings: The histogram shows that most movies in the dataset have IMDb ratings between 5.5 and 7.5. The distribution centers around 6.5, consistent with the mean of 6.46 and the median of 6.5.
Conclusion
The movies in this dataset show that IMDb ratings are predominantly centered on 6.5, with a mean of 6.46 and a median of 6.5. The ratings vary between 2.5 and 9.2, with a standard deviation of about 1.20. The majority of films, according to the histogram, have scores between 5.5 and 7.5. The distribution of IMDb ratings in this dataset is therefore clearly illustrated.