Other
Formula Sheet for Psychology 253
- Course
- Institution
- Book
This document holds all the relevant formulas that you will use and what each one is used for without confusing you.
[Show more]
Connected book
Book Title:
Author(s):
- Edition:
- ISBN:
- Edition:
More summaries for
-
Test Bank to Accompany Essentials of Statistics for The Behavioral Sciences,Gravetter,9e
-
Official© Solutions Manual to Accompany Essentials of Statistics for The Behavioral Sciences,Gravetter,9e
-
Empower Your Learning with the [Essentials of Statistics for The Behavioral Sciences, Gravetter,9e] 2024 Test Bank
Seller
Follow
Demanio
Reviews received
Content preview
Formula SheetPlease note: it is important to go through the lecture podcasts as these notes do not
serve as an alternative to them. Please don’t send my notes to anyone because I worked
really hard to make these as in depth and easy to understand as possible :)
Formula What it does
∑𝑓 = N The sum of the frequencies gives the total
number of individuals
p= 𝑓 ÷ N (work out proportion)
P (100) = (𝑓 ÷ N) x 100 (work out percentages)
Rows = highest - Lowest +1 (to find the no. of rows required for a
grouped freq. graph)
𝜇 = ∑X ÷ N (work out the mean for a population)
M = ∑X ÷ n (work out the mean for a sample)
(∑X₁ + ∑X₂) ÷ (n₁ + n₂) (work out overall or weighted mean)
Fraction = (number needed to reach 50%) ÷ (number in (work out precise median)
the interval)
Range = Xmax-Xmin (range)
Xmax-Xmin +1 (range if all the scores are whole
numbers)
X-𝜇 (work out deviation)
√variance (work out standard deviation)
Variance = mean squared deviation = (sum of squared Work out Variance
deviations) ÷ (number of scores)
Definitional formula: SS = ∑( X-𝜇)² (calculate Sum of Squares for
population)
Computational formula : SS= ∑X² - ((∑X)² ÷ N) (calculate sum of squares when
deviation contains decimals/ fractions)
SS ÷ N (work out population variance)
√ (SS ÷ N) (work out population standard
deviation)
Definitional formula: SS= ∑ (X - M)² (work out Sum of Squares for sample)
Computational formula: SS= ∑X² - ((∑X)² ÷ n) Work out sum of Squares for sample if
decimals and fractions are involve
s² = SS ÷ (n-1) Work out sample variance
Notes by: Michaela Goncalves
22587934
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller Demanio. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for CA$5.36. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
82871 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now