Cost per No. of Applications

The Study

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Explanation

Introduction to Your Study
Throughout this tutorial, we will use real data from a real experiment to illustrate the topics that you will learn about.

This tutorial relates the salary cost in dollars for an HR representative to the number of employment applications processed.

We will use the vocabulary of statistics, which can be confusing if you haven't seen it before, so here is an introduction to the study you will be working through and the words that are used to describe it.

The Data
Statistics are designed to help us understand things we observe in the world around us. To use statistics, we have to measure things in the real world and so produce data. Data can be expressed as words or numbers, and are plural - so you say "Here are my data."

So that we know which aspects of the data we are talking about, we use the following words:

  • To generate data we take measurements or make observations of specific qualities of things;
  • The things we are measuring are called the experimental units of the study. They might be referred to as 'people' or 'soil samples', whatever is being measured, but in this study, they are referred to as Applications;
  • The qualities that we measure, or observe, are called variables. So if you measured a piece of string, the string would be the experimental unit and 'length' would be the variable;
  • All variables take a range of values - the variable 'length' might take the values 3 or 10.5, for example. Generally, one measurement of a variable from a single experimental unit will produce a single value. If we say "Length = 5" then 'length' is the variable and '5' is the value.

Your study measured two variables: Cost, measured in Dollars and No. Apps, measured in Applications

The Study
Your study is looking for a relationship between two variables. You want to know if, and how strongly no. apps and cost are related.

Exploration

Here is the data from your study. Hover over the hightlighted parts of the table to find out how they relate to the description above.
Cost (Dollars)No. Apps (Applications)
715
66362
980110
13812
86183
14541
49346
54875
25123
1024100
43541
77275
7110
66359
38162
13815
86178
14559
49356
54856
25127
1009110
43546
772110
49346
54872
25123
988100
43541
66359

Application

Let's look at your data now and check that you have understood the concepts described above.
We are measuring cost and no. apps in your data. Which of the words in the box to the left best describes cost and no. apps?   Help
Read the sentence below and label the bold words
The first cost measured is 71 Dollars
Which of these words best describes cost?   Help
Which of these words best describes 71?   Help
Instructions | Frequency Histograms