Title: OA 7 Categorial Analysis
Course: PSYC 301 Statistical Methods in Psychol > Section: Last Part of Course

Dr. Werner is an Environmental Psychologist* who has studied the relationship between persons decorating and entry set up on the front of their homes and their social relationships in their neighborhood.** Imagine you are a new undergraduate student working with Dr. Werner and want to learn if the decoration of homes at Christmas season is related to those persons likelihood of greeting a visitor with an open door in the subsequent spring. Random houses were selected in a Northern Virginia neighborhood suburb of the DC Metro area. The address was recorded and the house was photographed one week prior to Christmas. These photographs were used to classify houses as being not decorated or decorated (the degree of decoration was not evaluated). In early April of the next year between 6 and 8 p.m., male-female (presenting) pairs of students approached each house and knocked on the door and rang the doorbell once. They then waited approximately 2 minutes for someone to answer the door. They noted if a person answered them with opening of the door, or not opening the door (no answer and answering with a closed door are treated as the same response). The results are presented below. Note that homes that were sold between the two measurements were removed from the analysis, determined by use of Zillow.com.

You are to use the linked data file (DoorOpening.omv) to do a Chi-Square Test of Independence in jamovi to test this research hypothesis:

Persons who have Christmas Decorations displayed at Christmas are more likely to open their door to strangers knocking at the door in Spring.

In the response text box provide responses to the following questions.

1. What is the value of the calculated Chi-square statistic?
2. What is the degrees of freedom of the test?
3. What is the probability of the calculated Chi-square statistic?
4. What decision do you make about the NULL hypothesis?
5. Please interpret your decision about the null hypothesis in terms of the above research hypothesis. Said differently, what does the decision mean in terms of the relationship between displaying decorations and people opening their doors when strangers knock?

Enjoy!

*An Environmental Psychologist studies how natural and human-built environments affect thinking and behavior and are affected by human thinking and behavior.

** https://www.sciencedirect.com/science/article/abs/pii/S0272494489800106