summarizing data/ data gathering

Question 1

objectives

Answer 1

By the end of the lecture students will:
 Explain and calculate measures of variation
 Describe the characteristics of the normal curve
 Apply the normal curve to research questions.
 Describe non-normal distributions.
 Outline ways of presenting data
 Explain which types of graphs are appropriate for different data sets

Question 2

what is Descriptive statistics?

Answer 2

Descriptive statistics
Refers to a branch of statistics that involves summarizing, organizing, and presenting data meaningfully and concisely.

It focuses on describing and analyzing a dataset’s main features and characteristics without making any generalizations or inferences to a larger population.

Question 3

what are the 3 branches of descriptive statistics?

Answer 3

1. central central tendency
2. variability or the spread of inputs
   3.frequency distribution

Question 4

What is central tendency?

Answer 4

The statistical measure that identifies a single value as representative of an entire distribution

It aims to provide an accurate description of the entire data. It is the single value that is most typical/representative of the collected data.

Question 5

what are the central tendency measures? 3 of them

Answer 5

M’s of central tendency :
mean-average data set

median-Middle value

mode- the measure that occurs the most

Question 6

Mean

Answer 6

Mean: Average of the data set
m = Sum of data set
Number of data

Question 7

Median

Answer 7

Median: The middle of the data set
Order values from smallest to largest
Median = [(n+1)/2]the observation
e.g
step 1: 1, 5, 7, 8, 9, 22, 43, 56, 76
step 2 Median = [(9+1)/2]th observation = 5th observation

Question 8

Mode

Answer 8

Mode: the most frequently occurring number in a data set

Question 9

Measures of Variability

Answer 9

Variability describes how far apart data points lie from each other and from the center of a distribution or the spread of data

Question 10

2 variability measures that determine spread?

Answer 10

range
standard deviation
distribution width

Question 11

Range and standard deviation require what data***

Answer 11

ratio and interval data

Question 12

what is the range?

Answer 12

The distribution of the 2 endpoints
range = {highest-lowest}

Question 13

what is the standard deviation

Answer 13

show how far the data points fall from the mean
large spread- more variability ftom the mean
small spread-less variability closer to the mean

**if negative square it
***take square root to remove square

Question 14

2 deviation formulas

Answer 14

population
and standard

Question 15

population standard deviation

Answer 15

σ = population standard deviation
xi = individual score
µ = sample mean
n = the number of scores in the distribution

Question 16

sample standard deviation
contains bessels correction

Answer 16

s = standard deviation
xi = individual score
𝒙̅ = sample mean
n-1 = the number of scores in the distribution

Question 17

normal curve involve

Answer 17

parametric data