University:
York University
Course:
PSYC 2021 | Statistical Methods I
Academic year:

2024
Views:

288

Pages:

3
Author:

Nick T.

Chapter one Why learn Statistics? • Increase your understanding of research articles • help you learn how to do your own research • Can improve your reasoning and intuition What is Statistics? • a branch of mathematics that focuses on the organization, analysis, and interpretation of a group of numbers goals of Statistical procedures - accurate and meaningful interpretation -Standardized evaluation procedures Basic Concepts • Variable -Characteristics or condition that can have different values eg., level of stress • Data (plural) -measurements or doservations of a variable Data Set -a collection of measurements or observations Datum (singular) •a Single measurement or observation - - Commonly called a score or raw score Sample vs. Population • Population -the set of all the individuals of interest in a particulour Study - vary in size; often quite large • Sample - a set of individuals selected from a population Usually intended to represent the population in a research study Parameters and Statistics • Parameter - a valve, usually a numerical valve, that describes a population includes all people from population • Statistic a valve, usually a numerical valve, that describes a Sample includes subset of population Sampling Error • Sample is never identical to population. Sampling error the discrepancy, or amount of error, that exists between a sample Statistic and the corresponding population parameter • Example: Margin of error in palls "this poll was taken from a sample of registered voters and has a margin of error of plus-or-minus 4 percentage points" Descriptive vs. Inferential Statistics • Descriptive Statistics Summarize data - organize data - Simplify data • Inferential Statistics - Study samples to make generalizations about the population interpret experimental data •Learning Check A researcher is interested in the effect of amount of sleep on high School students' exam Scores. A group of 75 high School boys agree to participate in the study. The 75 boys are... a) a Statistic b) a variable c) a parameter d) a Sampie Kinds of Variables • Discrete variable - has separate, indivisible categories - no values can exist between two neighboring categories • Continuous variable - has an infinite number of possible values between any two observed values - every Parts interval is divisible into an infinite number of fractional - Can have decimals