PSY516 Highlighted Handouts Lectures 1-22

Statistics in Psychology (PSY516)

Table of Content

Lesson no.

Title

Page no. Introduction to Statistics-I Introduction to Statistics-II Correlation Method Experimental and Non-experimental Method Introduction to SPSS

Frequency Distribution-I Frequency Distribution-II Measure of Central Tendency-I Measure of Central Tendency-II Measure of Variability-I Measure of Variability-II Z-scores Introduction to Probability-I Introduction to Probability-II Introduction to Probability-III Sampling Distribution Confidence Interval-I Confidence Interval-II Hypothesis Testing-I Hypothesis Testing-II Hypothesis Testing-III

Lesson 1 INTRODUCTION TO STATISTICS IN PSYCHOLOGY-I

Introduction to Statistics

The study of statistics is gaining recognition in a great many fields. In particular, researchers in the social, behavioral and health sciences note its importance for problem solving and its practical importance in their areas. Statistics is a science that enables us to draw conclusions about various phenomena on the basis of real data collected on sample-basis. It is a tool for databased research and also known as Quantitative Analysis. It is the science of collecting and learning from data. It is a branch of mathematics concerned with the collection, classification, analysis, and interpretation of numerical facts, for drawing inferences on the basis of their quantifiable likelihood (probability). Statistics also allows the researcher to interpret grouped data, too large to be intelligible by ordinary observation. Statistics has a lot of application in a wide variety of disciplines i.e. Agriculture, Anthropology, Astronomy, Biology, Economic, Engineering, Environment, Geology, Genetics, Medicine, Physics, Psychology, Sociology, Zoology…. Virtually every single subject from Anthropology to Zoology …. A to Z! Any scientific enquiry in which you would like to base your conclusions and decisions on reallife data, you need to employ statistical techniques. Now a days, in the developed countries of the world, there is an active movement for Statistical Literacy.

Defining Statistics

The term statistics refers to a set of mathematical procedures for organizing, summarizing, and interpreting information. One goes through the four stages of statistics:

1. Collection of data,
2. Organizing and summarizing the data,
3. Analysis of data, and
4. Making inferences, or decisions and predictions.

Stage four is the core objective of statistics in psychology, i.e., making inferences about a population based on information contained in a representative sample taken from that population. Statistics consist of facts and figures such as average income, crime rate, birth rate, baseball batting averages, and so on. These statistics are usually informative and time saving because they condense large quantities of information into a few simple figures. Statistics is the science of learning from data. Statistical procedures help to ensure that the information or observations are presented and interpreted in an accurate and informative way. In somewhat grandiose terms, statistics help researchers bring order out of chaos. Specifically, statistics serve two general purposes:

1. It is used to organize and summarize the information so that the researcher can see what happened in the research study and can communicate the results to others.
2. It helps the researcher to answer the questions that initiated the research by determining exactly what general conclusions are justified based on the specific results that were obtained.

Research in psychology (and other fields) involves gathering information. To determine, for example, whether violence on TV has any effect on children’s behavior, you would need to gather information about children’s behaviors and the TV programs they watch. When researchers finish the task of gathering information, they typically find themselves with pages and pages of measurements such as IQ scores, personality scores, reaction time scores, and so on.

Importance Of Statistics

As it is such an important area of knowledge, it is definitely useful to have a fairly good idea about the way in which it works, and this is exactly the purpose of this introductory course. The following points indicate some of the main functions of this science: Statistics assists in summarizing the larger set of data in a form that is easily understandable. Statistics assists in the efficient design of laboratory and field experiments as well as surveys. Statistics assists in a sound and effective planning in any field of inquiry. Statistics assists in drawing general conclusions and in making predictions of how much of a thing will happen under given conditions.

Importance Of Statistics In various fields

As stated earlier, Statistics is a discipline that has finds application in the most diverse fields of activity. It is perhaps a subject that should be used by everybody. Statistical techniques being powerful tools for analyzing numerical data are used in almost every branch of learning. In all areas, statistical techniques are being increasingly used, and are developing very rapidly.