Calculate cutoff values and analyzing histograms, Advanced Statistics

Assignment Help:

1. You are interested in investigating if being above or below the median income (medloinc) impacts ACT means (act94) for schools. Complete the necessary steps to examine univariate grouped data in order to respond to the questions below. Although deletions and/or transformations may be implied from your examination, all steps will examine original variables.

a. How many subjects have missing values for medlonic and act94?

b. Is there a severe split in frequencies between groups?

According to the descriptive analysis, no severe split is detected. This is also reflected in the skewness number which is lower than .5.

c. What are the cutoff values for outliers in each group?

d. Which outlying cases should be deleted for each group?

Average ACT score 1994 Stem-and-Leaf Plot for

medloinc= below the median for low inc % 1993

 Frequency Stem & Leaf

 7.00 14 . 1223789

 9.00 15 . 234478888

 5.00 16 . 12788

 4.00 17 . 1378

 2.00 18 . 09

 1.00 19 . 6

 3.00 20 . 069

 1.00 Extremes (>=22.5)

 Stem width: 1.0

 Each leaf: 1 case(s)

e. Analyzing histograms, normal Q-Q plots, and tests of normality, what is your conclusion regarding normality? If a transformation is necessary, which one would you use?

Tests of Normality

 

above or below median loinc

Kolmogorov-Smirnova

Shapiro-Wilk

 

Statistic

df

Sig.

Statistic

df

Sig.

average ACT score 1994

below the median for low inc % 1993

.162

32

.032

.903

32

.007

above the median for low inc % 1993

.166

32

.025

.921

32

.023

 

According to the information and the test of normality, it appears that this is a normal distribution.  Therefore, for the transformation, we would select 'Square Root."

 

 

f. Do the results from Levene's Test of Equal Variances indicate homogeneity of variance? Explain.

In running the test, there were no significant differences between the categories. Therefore; we can assume that this indicates homogeneity of variance.

2. Examination of the variable of scienc93 indicates a substantial to serve positively skewed distribution. Transform this variable using the most two appropriate methods. After examining the distribution for these transformed variables, which produced the best alteration?


Related Discussions:- Calculate cutoff values and analyzing histograms

Chernoff''s faces, Chernoff's faces : A method or technique for representin...

Chernoff's faces : A method or technique for representing the multivariate data graphically. Each observation is represented by the computer-created face, the features of which are

Explain prevalence, Prevalence : The measure of the number of people in a p...

Prevalence : The measure of the number of people in a population who have a certain disease at a given point in time. It c an be measured by two methods, as point prevalence and p

Per-experiment error rate, Per-experiment error rate is the possibility of...

Per-experiment error rate is the possibility of the incorrectly rejecting at least one null hypothesis or assumption in the experiment including one or more tests or comparisons,

Quittingill effect, Quittingill effect is a  problem which occurs most fre...

Quittingill effect is a  problem which occurs most frequently in studies of the smoker cessation where smokers frequently quit smoking following the onset of the disease symptoms

Back-projection, Back-projection: A term most often applied to the procedu...

Back-projection: A term most often applied to the procedure for reconstructing plausible HIV incidence curves from the AIDS incidence data. The method or technique assumes that th

Explain maternal mortality, Maternal mortality : The maternal death is the ...

Maternal mortality : The maternal death is the death of a woman while pregnant, delivering a baby or within 42 days of the termination of pregnancy, from any reason related to or a

Leaps-and-bounds algorithm, Leaps-and-bounds algorithm is an algorithm whi...

Leaps-and-bounds algorithm is an algorithm which is used to ?nd the optimal solution in problems which might have a large number of possible solutions. Begins by dividing the poss

Multivariate analysis of variance, Multivariate analysis of variance is th...

Multivariate analysis of variance is the procedure for testing equality of the mean vectors of more than two populations for the multivariate response variable. The method is dire

Behrens fisher problem, Behrens Fisher problem : The difficulty of testing ...

Behrens Fisher problem : The difficulty of testing for the equality of the means of the two normal distributions which do not have the equal variance. Various test statistics have

Cube law, A law supposedly applicable to voting behaviour which has a histo...

A law supposedly applicable to voting behaviour which has a history of several decades. It may be stated thus: Consider a two-party system and suppose that the representatives of t

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd