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

Explain kurtosis, Kurtosis: The extent to which the peak of the unimodal p...

Kurtosis: The extent to which the peak of the unimodal probability distribution or the frequency distribution departs from its shape of the normal distribution, by either being mo

Relative risk, Relative risk is the measure of the association between the...

Relative risk is the measure of the association between the exposure to a particular factor and the risk or probability of a convinced outcome, calculated as follows     therefor

Business forcastin.., elements , importance, limitation, and theories

elements , importance, limitation, and theories

Residual calculation, Regression line drawn as y= c+ 1075x ,when x was2, an...

Regression line drawn as y= c+ 1075x ,when x was2, and y was 239,given that y intercept was 11. Calculate the residual ?

Whites general heteroscedasticity test, The Null Hypothesis - H0:  γ 1 = γ...

The Null Hypothesis - H0:  γ 1 = γ 2 = ...  =  0  i.e.  there is no heteroscedasticity in the model The Alternative Hypothesis - H1:  at least one of the γ i 's are not equal

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,

Inliers, Inliers is the term used for the observations most likely to be s...

Inliers is the term used for the observations most likely to be subject to error in situations where the dichotomy is developed by making a ‘cut’ on an ordered scale, and where th

Non central distributions, Non central distributions is the series of prob...

Non central distributions is the series of probability distributions each of which is the adaptation of one of the standard sampling distributions like the chi-squared distributio

January 2015 Take-Home Assignment, 3. a. A researcher in Hong Kong computes...

3. a. A researcher in Hong Kong computes the correlation between the percentage of employee turnover and the local unemployment rate (also expressed as a percentage) over a 20-mont

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