My Math Forum  

Go Back   My Math Forum > High School Math Forum > Elementary Math

Elementary Math Fractions, Percentages, Word Problems, Equations, Inequations, Factorization, Expansion

LinkBack Thread Tools Display Modes
April 6th, 2018, 07:39 PM   #1
Joined: Apr 2018
From: Somewhere

Posts: 1
Thanks: 0

Question Working with a user survey.

We're currently working with a survey that allows our users to rate a set of items on a scale of one to seven. We're getting the weighted average for each item (rating multiplied by the number of people who submitted that rating, divided by the sum of all the ratings for that item). But, not all participants are answering all items. One person may rate 7 of the 15 available items, while another may rate 14, and so on. Does the variation in sample size/variation in the number of people answering per item matter here? We are looking to organize these from highest to lowest.
Lunatea is offline  
April 11th, 2018, 01:35 AM   #2
Joined: Mar 2018
From: Washington

Posts: 6
Thanks: 0

Math Focus: Geometry
You understand that all sampling options are on the Internet and are detailed for what purpose and how they are used. You understand that the most popular are random and quotas, sociologists are more aware of this. Here's what I found on your request. I hope this helps.

In mathematical terms, given a random variable X with distribution F, a random sample of length n (where n may be any of 1,2,3,...) is a set of n independent, identically distributed (iid) random variables with distribution F.[7]
A sample concretely represents n experiments in which the same quantity is measured. For example, if X represents the height of an individual and n individuals are measured, $X_{i}$ will be the height of the i-th individual. Note that a sample of random variables (i.e. a set of measurable functions) must not be confused with the realizations of these variables (which are the values that these random variables take). In other words, $X_{i}$ is a function representing the measurement at the i-th experiment and $x_{i}=X_{i}(\omega)$ is the value obtained when making the measurement.

The concept of a sample thus includes the process of how the data are obtained (that is, the random variables). This is necessary so that mathematical statements can be made about the sample and statistics computed from it, such as the sample mean and covariance.

Last edited by skipjack; April 11th, 2018 at 02:11 AM.
ScottyBlack228 is offline  

  My Math Forum > High School Math Forum > Elementary Math

survey, user, working

Thread Tools
Display Modes

Similar Threads
Thread Thread Starter Forum Replies Last Post
L'Hôpital rule not working correctly? Well, probably it is me who is working wrongly srecko Calculus 5 December 13th, 2016 08:00 PM
Places Survey Eminem_Recovery New Users 35 March 8th, 2011 04:29 AM
AGE SURVEY HELP! Francis410 New Users 6 December 13th, 2010 11:58 AM

Copyright © 2019 My Math Forum. All rights reserved.