In a study to determine whether an association exists between maternal rubella and congenital cataracts, samples...

In a study to determine whether an association exists between maternal rubella and congenital cataracts, samples of 20 children with congenital cataracts and 25 children without congenital cataracts were selected. The mother of each child was asked whether she had rubella while carrying the child. The data are given below. Assume that all z-based methods are valid.


RUBELLA	CATARACTS
Frequency Row Pct	1_YES	2_NO	Total
1_YES	14 58.33	10 41.67	24
2_NO	6 28.57	15 71.43	21
Total	20	25	45

Statistic	DF	Value	Prob
Chi-Square	1	4.0179	0.0450
Likelihood Ratio Chi-Square	1	4.0979	0.0429
Continuity Adj. Chi-Square	1	2.9029	0.0884
Mantel-Haenszel Chi-Square	1	3.9286	0.0475
Phi Coefficient		0.2988
Contingency Coefficient		0.2863
Cramer's V		0.2988

Column 1 Risk Estimates
	Risk	ASE	95% Confidence Limits		Exact 95% Confidence Limits
Row 1	0.5833	0.1006	0.3861	0.7806	0.3664	0.7789
Row 2	0.2857	0.0986	0.0925	0.4789	0.1128	0.5218
Total	0.4444	0.0741	0.2993	0.5896	0.2964	0.6000

Difference	0.2976	0.1409	0.0215	0.5737
Difference is (Row 1 - Row 2)

What are the null and alternative hypotheses? Be sure to define any symbols that you use.

Solutions

Expert Solution

The Chi-Square test of independence is used to determine if there is a significant relationship between two nominal (categorical) variables. The frequency of each category for one nominal variable is compared across the categories of the second nominal variable.

First we have to calculate the expected value of the two nominal variables. We can calculate the expected value of the two nominal variables by using this formula:

Where

= expected value

= Sum of the ith column

= Sum of the kth row

N = total number

After calculating the expected value, we will apply the following formula to calculate the value of the Chi-Square test of Independence:

= Chi-Square test of Independence
= Observed value of two nominal variables
= Expected value of two nominal variables

Null hypothesis: Assumes that there is no association between maternal rubella and congenital cataracts

Alternative hypothesis: Assumes that there is an association between maternal rubella and congenital cataracts

orchestra answered 1 year ago

Next > < Previous

Related Solutions

. In a study to determine whether an association exists between maternal rubella and congenital cataracts,...

. In a study to determine whether an association exists between maternal rubella and congenital cataracts, samples of 20 children with congenital cataracts and 25 children without congenital cataracts were selected. The mother of each child was asked whether she had rubella while carrying the child. The data are given below. Assume that all z-based methods are valid. RUBELLA CATARACTS Frequency Row Pct 1_YES 2_NO Total 1_YES 14 58.33 10 41.67 24 2_NO 6 28.57 15 71.43 21 Total 20...

The manager of a telemarketing call centre wishes to determine whether an association exists between the...

The manager of a telemarketing call centre wishes to determine whether an association exists between the communicating time of its employees and the level of stress-related problems observed on the job. A study of 100 employees reveals the following: stress stress stress Commuting time (High) (Moderate) (low) 20 mins and under 15 12 33 over 20 mins 25 8 7 At the 5% level of significance, is there evidence of a significant relationship between commuting time and stress?

You are conducting a case control study to determine if an association exists between melanoma and...

You are conducting a case control study to determine if an association exists between melanoma and indoor tanning. From a statewide cancer registry, you identify 1,107 people who were diagnosed with melanoma during the last three years. You select 1,500 controls for your study. Through a follow-up survey, you find that 696 of those with melanoma had a history of indoor tanning. 48.2% of the control group reported no exposure to indoor tanning. Part I: Calculate the odds ratio. Part...

Q5. [20] We would like to determine whether any association exists between the survival time and...

Q5. [20] We would like to determine whether any association exists between the survival time and level of water toxicity, region and age of the patients. Survival time is coded as 1 if < 1 month, 2 = 1-3 months, and 3 = more than 3 months. Survival Region Toxic Level Age 1 1 62.00 67 1 2 46.00 72 2 1 48.50 56 3 2 32.00 35 2 1 63.50 60 1 1 41.25 65 2 2 40.00 45...

A research conducts a study to determine whether there is an association between time students spent...

A research conducts a study to determine whether there is an association between time students spent on revising the exam and level of level of exam anxiety among undergraduate. The researcher recruited 10 nursing students. To help the researcher, you need to do the hand calculation and then you use the SPSS Time spent revision Exam anxiety .40 10 1.30 9 2.15 8.5 3.40 6 4.30 1.5 4.00 3 3.45 5 2.30 7 2.00 8.5 1.15 9

A research study was conducted to assess whether there is an association between stress disorders in...

A research study was conducted to assess whether there is an association between stress disorders in pregnancy and autism spectrum disorders (ASD) in their children born out of these pregnancies. Forty children with ASD and fifty without ASD were selected for investigation. Mothers were asked about whether they suffered from stress disorders during their pregnancy. This study is an example of a:3 a. Prospective cohort study b. Retrospective cohort study c. Case control study d. Randomized controlled trial

An emergency service wishes to determine whether a relationship exists between the outside temperature and the...

An emergency service wishes to determine whether a relationship exists between the outside temperature and the number of emergency calls it receives for a 7-hour period. The data are shown. (25 points) Temperature x 25 10 27 30 33 No. of calls y 7 4 8 10 11 a) Find the correlation coefficient r (If you use any software or online calculator, please take the screenshot. You will get extra points if you do by hand.) b) Find the regression...

In an effort to determine whether any correlation exists between the price of stocks of airlines,...

In an effort to determine whether any correlation exists between the price of stocks of airlines, an analyst sampled six days of activity of the stock market. Using the following prices of Delta stock and Southwest stock, compute the coefficient of correlation. Stock prices have been rounded off to the nearest tenth for ease of computation. Delta Southwest 47.6 15.1 46.4 15.4 50.6 16.1 52.6 15.6 52.4 16.4 53.2 18.1

A study was undertaken to determine the strength of association between several risk factors and the...

A study was undertaken to determine the strength of association between several risk factors and the duration of pregnancies. The risk factors considered were mother's age, nutritional status, history of tobacco use, and history of alcohol use. The response of interest, pregnancy duration is a three-categories variable that was coded as follows: Yi Pregnancy Duration Category 1 Preterm 2 Intermediate term 3 Full term We would like to study the association between the duration of pregnancy and risk factors. (a)...

Investigators conducted a case control study to determine if there was an association between asthma symptoms...

Investigators conducted a case control study to determine if there was an association between asthma symptoms and exposure to dust (dust or no dust). They collected information from 62 matched pairs of cases (those experiencing asthma symptoms) and controls (those not experiencing asthma symptoms). They entered their observed counts in SAS using the code below: data study; input case $ control $ count @@; cards; dust dust 10 dust no_dust 35 no_dust dust 12 no_dust no_dust 5 ; run; a)...

Subjects