https://github.com/ndaidong/average-rating
Calculate average score and rating based on Wilson Score Equation
https://github.com/ndaidong/average-rating
rating rating-stars rating-system scoring wilson-score-equation
Last synced: 6 months ago
JSON representation
Calculate average score and rating based on Wilson Score Equation
- Host: GitHub
- URL: https://github.com/ndaidong/average-rating
- Owner: ndaidong
- License: mit
- Created: 2015-11-05T14:32:33.000Z (almost 10 years ago)
- Default Branch: main
- Last Pushed: 2024-06-23T10:29:30.000Z (over 1 year ago)
- Last Synced: 2025-04-13T15:41:49.535Z (6 months ago)
- Topics: rating, rating-stars, rating-system, scoring, wilson-score-equation
- Language: TypeScript
- Size: 115 KB
- Stars: 33
- Watchers: 2
- Forks: 7
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- License: LICENSE
Awesome Lists containing this project
README
# average-rating
Calculate average and scoring based on Wilson Score Equation
[](https://github.com/ndaidong/average-rating/actions)
[](https://coveralls.io/github/ndaidong/average-rating)
[](https://www.npmjs.com/package/@ndaidong/average-rating)
[](https://jsr.io/@ndaidong/average-rating)
## Setup & Usage
### Deno
https://jsr.io/@ndaidong/average-rating
```sh
deno add @ndaidong/average-rating
# npm (use any of npx, yarn dlx, pnpm dlx, or bunx)
npx jsr add @ndaidong/average-rating
```
```ts
// es6 module
import { average, rate, score } from "@ndaidong/average-rating";
// CommonJS
const {
score,
rate,
average,
} = require("@ndaidong/average-rating");
score(80, 20); // => 0.71
rate([134055, 57472, 143135, 365957, 1448459]); // => 0.84
average([134055, 57472, 143135, 365957, 1448459]); // => 4.4
```
You can use JSR packages without an install step using `jsr:` specifiers:
```ts
import { average } from "jsr:@ndaidong/average-rating";
average([134055, 57472, 143135, 365957, 1448459]); // => 4.4
```
You can also use `npm:` specifiers as before:
```ts
import { average } from "npm:@ndaidong/average-rating";
average([134055, 57472, 143135, 365957, 1448459]); // => 4.4
```
Or import from esm.sh
```ts
import { average } from "https://esm.sh/@ndaidong/average-rating";
average([134055, 57472, 143135, 365957, 1448459]); // => 4.4
```
### Node.js & Bun
https://www.npmjs.com/package/@ndaidong/average-rating
```bash
npm i @ndaidong/average-rating
# pnpm
pnpm i @ndaidong/average-rating
# yarn
yarn add @ndaidong/average-rating
# bun
bun add @ndaidong/average-rating
```
```ts
import { average } from "@ndaidong/average-rating";
average([134055, 57472, 143135, 365957, 1448459]); // => 4.4
```
You can also use CJS style:
```ts
const { average } = require("@ndaidong/average-rating");
average([134055, 57472, 143135, 365957, 1448459]); // => 4.4
```
### Browsers:
```html
import { average } from "https://esm.sh/@ndaidong/average-rating";
// import { average } from 'https://unpkg.com/@ndaidong/average-rating/esm/mod.js';
average([134055, 57472, 143135, 365957, 1448459]) // => 4.4
```
## APIs
### .score(Number positive, Number negative)
This method returns a normalized value between 0 and 1, but it's applicable for systems
with only positive and negative ratings (like/dislike, thumbs up/thumbs down).
Examples include videos on YouTube or answers on Stack Overflow.
In these systems, users can express their opinion by voting for either a positive or negative option.
Let's illustrate how this method works with a blog post that received 80 likes and 20 dislikes:
```ts
import { score } from "@ndaidong/average-rating";
score(80, 20); // => 0.71
```
### .rate(Array ratings)
This method returns a normalized value between 0 and 1, commonly used in rating systems with 5 levels.
Examples include applications on Google Play Store or books on Amazon.
In these systems, each item receives a user rating between 1 and 5 stars.
Let's take a product with a large volume of reviews as an example. Here's how we calculate its rating:
- 134,055 customers rated it 1 star
- 57,472 gave it a 2-star rating
- There are 143,135 ratings of 3 stars
- It received a 4-star rating from 365,957 users
- And a whopping 1,448,459 customers rated it 5 stars
```ts
import { rate } from "@ndaidong/average-rating";
rate([134055, 57472, 143135, 365957, 1448459]); // => 0.84
```
##### Update
- Since v1.1.5, this `rate` method accepts custom range of ratings. 5 or more
values are OK.
```ts
const input = [3, 4, 2, 6, 12, 46, 134, 213, 116, 91, 45, 15, 58, 96, 1654]; // 15 values
rate(input); // => 0.85
rate([3, 4, 2, 6, 12, 46, 134, 213, 116, 91]); // => 0.74
```
### .average(Array ratings)
Return a value from 0 to 5.
Calculate normal average value for the systems of 5 rating levels.
```ts
import { average } from "@ndaidong/average-rating";
average([134055, 57472, 143135, 365957, 1448459]); // => 4.4
```
## Development
Since v3.x.x, we switched to [Deno](https://docs.deno.com/runtime/manual/)
platform, and use [DNT](https://github.com/denoland/dnt) to build Node.js
packages.
```bash
git clone https://github.com/ndaidong/average-rating.git
cd average-rating
# test
deno test
# build npm packages
deno task build
cd npm
node test_runner.js
```
# License
The MIT License (MIT)
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