June 2020
Did you know that according to the World Health Organization, an estimated 12 million people worldwide die each year from heart related diseases and paralysis? Heart disease is a major cause of death worldwide. But it is also important to note that much can be done to prevent this disease. 

10 Ways To Take Care Of Your Heart

World over, people usually takes cholesterol pills to prevent this disease, which costing billions of dollars annually. Moreover, 736 million (2015 estimate) poor people of the world cannot afford this expensive treatment for heart diseases.

In these circumstances, it is natural to accept the phrase, "Prevention is better than cure." Before we learn how to avoid heart diseases, let's have a simple understanding of types of heart disease.



Types of Heart Diseases

(1) Atherosclerotic Disease

In this type of heart disease, layers of fat, calcium, cholesterol, etc. accumulate in the arteries and block the blood flow.

(2) Cardiac Arrhythmia

In this type, the rate of beating the heart becomes too high or too low.

(3) Heart Valve Disease

The human heart consist four valves. In this type of disease the valve is surrounded by two types of problems. The first problem is that the blood flow in the valve is partially blocked (called stenosis) while in the second problem the blood flow from the valve starts leaking and turns in a direction other than the specific one.

(4) Heart Infections

This problem usually affects people over 60 years of age. In which there is an infection in the heart, causing swelling on the valves and arteries. Swelling often occurs on the internal heart muscles.

(5) Heart Failure

Heart failure simply means the blood supply to the human body stops. This is the widely known problem of heart disease, and also the most fatal one.

After knowing the above details, let's look at the following simple tips that will help you to avoid a heart related diseases. 

Ten amazing tips:

(1) Eat Mediterranean Food


According to a survey, people living in countries around the Mediterranean have a much lower rate of heart disease than others. The people there eat vegetables, fish, garlic, olive oil and often drinks a little red wine. You don't need to be a European to follow  European principles in the diet.

2) Eat Tomatoes

Eat plenty of tomatoes. The reddish color found in tomatoes is due to the Lycopene in them. Tomatoes are strong antioxidant. In addition, research has shown that tomatoes help lower blood pressure and C-reactive protein, which reduces the risk of heart disease.

3) Laugh


An experiment was performed with few volunteers. These volunteers were shown Funny videos.Volunteers who laughed at these funny videos found with relieved blood vessels. Laughter lowers blood pressure, as it relieves stress. So find a way to laugh now and then. So, Laugh and make people laugh with you.

4) Include Fiber in Diet

Use plenty of fiber in the diet. It is well known that fiber is very useful for the intestines and for the proper functioning of the digestive system. Eat a diet rich in fiber, a diet rich in fiber helps to keep the heart healthy.

5) OK to exercise little but do it regularly 

Usually people don't exercise in today's race. It is harmful to health. Even if a little exercise is done according to the convenience of the person, it should be done regularly. Let's do a very good exercise. Get up and walk 100 steps. Do this often. One of the best exercise is yoga, in which you can do various Asanas. Moreover, in yoga itself, sun salutation has been the basis of life since ancient times. Do it. Don’t know how to perform the Surya Namaskar (Sun Salutation) Don’t worry, you can follow the link below: 

Surya Namaskar a classical form of Yoga

6) Take a Sun bath


The Sun is the basis of life on Earth. Nature uses the power of the Sun. The human body gets vitamin D from the sun's rays. Did you know that people with low levels of vitamin D are more susceptible to heart disease? Spend 10 minutes on a few days each week and take advantage of nature's gift.

7) Let me say you something you all like: “Eat Chocolate”

The Polyphenols in dark chocolate help increase good cholesterol and reduce bad cholesterol. Some studies have suggested that a person with a heart attack improves their condition faster if they consume a little chocolate every day. How much chocolate to consume? Well, you only need to eat about 40 grams chocolates per day that contains 70% cocoa.

8) Stress Management

It is not wrong to say that today’s time is the time of mental stress. These days even young children are falling a victim of stress. Stress increases the risk of heart attack by 30%. Therefore, managing stress is very important. Yoga-meditation came to mind again. The Pranayama and meditation shown in yoga are really very beneficial in mental stress. Now you may find some trace management class in your cities, you can also attain it. Walking for 30 minutes is an easy way to reduce stress.

9) Let's do Tai-Chi


People who do regular Tai-Chi have lower blood pressure and heart disease rates.

10) Be positive

There is no guarantee of life and even if we do all the "right" things we can get sick. Even if you have a heart attack, long-term survival and quality of life can be improved by adopting an optimistic outlook of life. To say positive here does not mean to be unreal at all. 

If you use the very simple principles mentioned above, it is very likely that you will not have heart problems and those who have had to rely on pills due to heart problems will be able to reduce that dependence and enjoy good health.
American Constitution
American Constitution
The American Constitution is the constitution of United State of America. It was formed in 1787 after the famous American Revolution (1775-83).

In the year 1787, it was adopted at Philadelphia Convention and came into force in 1789. 

American Constitution
Philadelphia Convention
Now let’s we look into the some of the main characteristics of the American Constitution mentioned below:

Black and White (Written) Constitution

American constitution is classic example of written constitution. It’s the oldest among written constitution of the world. So, what it contains:
  • Some 12 pages

  • A Preamble

  • 7 Articles

  • 27 Amendments.

Apart from above it also includes actual working constitutional system like…

(1) Status of Congress ( Legislature of United States)

(2) The orders (Executive Orders) issued by the President, giving practical shape to statues made by Congress.

(3) Judicial decisions interpreting the constitution through a system like Judicial Review (Implied power)

(4) The political conventions. (E.g., cabinet of the president)

Rigid Constitution

Unlike flexible constitution of some countries like of Britain, American constitution is most rigid in the world. If it required to be amend it can be done so by Congress only and by the means of special process described in the constitution. So, in USA there is clear difference between ordinary law and constitutional law.

Two methods for constitutional amendment are listed below:

1. An amendment can be proposed by 2/3 votes of both the house of Congress. It also need to be ratified by the legislature of ¾ (38 out of 50) of the states within a seven year time span.

2. An amendment can be proposed by convention called by the Congress on the petition of 2/3 (30 of 50) of the state legislature. It needs the ratified by the convention in ¾ (38 of 50) state legislature.

Hence, the procedure to amend American constitution is very difficult. It also evident from the fact that only 27 times the constitution is amended since its inception in 1789.

Separation of Powers

The legislative, executive and judicial power of the government are clearly separated and vested in three independent organs of the Government- e.g.,

Article – I    Congress

Article-II     President

Article- III   Supreme Court and inferior courts

Presidential Government

USA adopted the presidential form of government. The main features of this follows:

1.  President is the head of state and head of government both. He is the chief real executive.
          As a Head of State – Ceremonial Position

          As a Head of Government - Executive Chief.

2.  Elected by electoral college for a fixed tenure of four years. He cannot be removed by the Congress except by the impeachment process described in constitution.

3. President governs with the help of small groups known as “Kitchen Cabinet”. The member in this group is selected and chosen by president and responsible to him only.

4. President and his secretaries are not responsible to the Congress for their act.

5. House of Representative cannot be dissolved by President.

Checks and Balances:

The principle of separation of powers gave a birth to checks and balances. Each organs of the government is interdependent to each other and that ensures that no organ becomes autocratic and irresponsible.


Key aspects of checks and balance:

1.   President Veto: Veto is of two types namely Pocket Veto and Qualified Veto

2.  Senate confirms higher appointment and international treaties made by the President.

3.  Congress has the power to determine the organization of judiciary.

4.  President appoints judge with a consent of the Senate.

5.  The Supreme Court can declare President or Congress laws as Ultra Vires (means null and void)

Federal Constitution

It is the first and the oldest federal constitution in the world. It comprises 50 states (13 original) and District of Columbia. Each state has its own constitution, legislative, governor and a supreme court.

Bill of Rights

The first constitution in the world that carried the bill of rights. It assures the large number of rights to the American people.

No person is to be deprived of life, liberty and property without the due process of law. This rights also curtails the absolute authority of government. Supreme Court acts as a guardian of these rights by judicial review. These rights were added in the constitution in 1791 through first ten amendments.

Bicameralism

The American Congress is bicameral that is, it consist of two houses:
  • The Senate (Upper House)
  • The House of Representative (Lower House)
Let’s understand the structure: 

Congress
Member
Duration
The Senate
100
Two being elected from each state to serve for a fixed term of six years
The House of Representative
435
Single member constituencies for a fixed two-year term

The Senate is more powerful then the House of Representative, infect, the Senate is the most powerful upper house in the world.

I hope now you understand the key concept of American Constitution. If you like this article please subscribe to my channel.
Surya Namaskar is classical form of Yoga. As we all know Yoga is the most ancient science of India. It constitutes important aspects of human life. Additionally, very effective way for weight loss.

It is considered a science as ancient as the human race. Yoga has the capacity to bring about fundamental transformation in the individual. In addition, it open the gate for new dimension of life.

Surya Namaskar


Yoga is a complete exercise that provides physical, mental as well as spiritual benefits. For instance, you can handle the stressful situations by understanding how to remain calm. It provides workout for the muscles. Moreover, it benefits joints, ligaments and the skeletal system by improving flexibility and balance.

Pranayam and aasnas is good for the heart and stimulates the fluid system of the body. Provides oxygen filled blood and helps strengthen the heart. It is good for the digestive system, the nervous system and breathing.

In today's stress full life, Yoga enables the various endocrinal glands to function properly and reduces tension and anxiety. If you are suffering from lack of sleep, Yoga will help you to sleep well. In other words, yoga is useful in many mind and body ailments.

Surya Namaskar sun salutation is an ancient form of yoga. This yoga form is an outright meditative technique which includes Aasnas and Pranayam. Surya Namaskar combines 12 different postures followed in a sequence with an exclusive breathing pattern.

Surya Namaskar certainly helps an individual to vitalize and unblocks the whole system. This form of yoga is great for weight loss and to reduces fat from almost all parts of the body as it stretches and tones each and every muscle. Remember it, it should be performed in the time of rising sun, facing the East.

Surya Namaskar steps: (Yoga Poses)

Surya Namaskar

There are total 12 asanas in Surya Namaskar (see picture below). Their benefits and Surya Namaskar mantra are also mentioned.

Surya Namaskar


1. Pranamasana (Prayer pose)

Stand with your feet together and palms folded in front of your chest. Close your eyes properly.

Benefits:

(Promotes balance, stimulates the breathing system, exercises shoulder, back and neck muscles.)

Mantra: Om Mitraaya Namaha

2. Hastauttanasana (Raised arms pose)

Raise your arms over your head and shoulders with the palms touching each other and biceps touching your ears. Stretch your bally as much as you can and just lean backwards.

Benefits:
 
(It strengthens balance, digestion, exercises arms and shoulder muscles, tones the spine and flexibility in back and hips.)

Mantra:Om Ravaye Namaha

3. Hastapadasana (Standing forward bend)

Lean forward and place your palms at the side of your feet. Touch your knee with forehead and exhale deeply.

Benefits:

(Promotes blood circulation, tones abdominal tracts, stretches back and leg muscles, stimulates spinal nerves, and stimulates lymphatic system.)

Mantra:Om Suryaya Namaha

4. Ashwa Sanchalanasana (Equestrian pose)

Now, one leg back and place the other leg in the front with palms fixed on the ground. Raise your head and inhale.

Benefits:

(Exercises spine, strengthens hand and wrist muscles.)

Mantra:Om Bhaanave Namaha

5. Dandasana (Stick pose)

Bring the leg next to the other one. Keep the hips off the floor with both your hands supporting the body in a push up position and Exhale.

Benefits:


(Stimulates blood circulation, strengthens the heart, strengthens wrist and arm muscles, relieves neck and shoulder tension.)

Mantra:Om Khagay Namaha

6. Ashtanga Namaskara (Salute with eight parts or points)

Bend your knees, chest and forehead firmly down along with your palms. Keeps the elbows bent upwards. Hold your breath here.

Benefits:

(It makes leg and arm muscles stronger, it improves flexibility in neck, shoulders and back muscles. It also releases tension in the neck and shoulder.)

Mantra:Om Pooshne Namaha

7. Bhujangasana (Cobra pose)

Drop your waist and raise your upper body. Look upwards and keep your arms straight. Then inhale at a slow pace.

Benefits:

(It energizes circulation to stomach organs and improves it. Help stretching upper and lower body, assists flexibility in the back and nerves in the spine.)

Mantra:Om Hirany Garbhay Namaha

8. Adho Mukha Svanasana (Downward facing dog poses)

Raise your hips and just bring your head to the floor and heel on the floor. This position will exactly look like an inverted 'V' then exhale.

Benefits:

(Stimulates blood circulation, strengthens the heart, strengthens wrist and arm muscles, relieves neck and shoulder tension.)

Mantra:Om Mareechaye Namaha

9. Ashwa Sanchalanasana (Equestrian pose)

In this step the posture is the same as the fourth step and inhale.

Benefits:

(Exercises spine, strengthens hand and wrist muscles.)

Mantra:Om Aadityay Namaha

10. Hastapadasana (Standing forward bend)

In this step the posture is the same as the third step and exhale.

Benefits:

(Strengthens blood circulation, tones abdominal tracts, stretches back and leg muscles, stimulates spinal nerves, and stimulates lymphatic system.)
 
Mantra:Om Savitre Namaha

11. Hastauttanasana (Raised arms pose)

This stage is same as the second stage and inhale.

Benefits:


(Strengthens balance, digestion, exercises arms and shoulder muscles, tones the spine, and it increase flexibility in back and hips.)

Mantra:Om Arkaay Namaha

12. Tadasana (Mountain Pose)

This stage is the final stage of Surya Namaskar and it is same to the first stage. You have to breathe normally here.

Benefits:


(Promotes balance, stimulates breathing system, exercises shoulder, back and neck muscles)

Mantra:Om Bhaskaray Namaha

Start performing Surya Namaskar from today, and feel the difference.

What is Skewness and types of skewness in Statistics?

Before understanding the types of skewness, let’s understand the meaning of skewness and frequency distribution first.

As we know every frequency distribution needs to be symmetrical or symmetrically distributed, but there are a lot of factors that affect the data, classification, and interpretation of variables.

These factors take the values far from the symmetry. Hence, this is known as skewness of frequency distribution.

The symmetrical frequency distribution is represented in the bell-shaped graph below:
 
types of skewness

Meaning of Skewness

The lack of symmetry of a frequency distribution is called skewness. In other words, a frequency distribution whose frequency curve is not bell-shaped is said to be skewed.

Meaning of Frequency Distribution

While doing the classification of data, values of variable under study are considered. This is known as classification of data or Frequency distribution.

Types of Skewness

The skewness of frequency distribution can be of two types:

(1) Positive Skewness 

 

(2) Negative skewness


Types of Skewness

It should be remembered that zero skewness is not considered one of the types of skewness, because a frequency distribution with zero skewness is not skewed but it is symmetric.

1. Positive Skewness or Positively Skewed Distribution

The frequency curve of the positively skewed frequency distribution is as shown in the above diagram-

A frequency distribution in which the values of the mean, median, and mode are in descending order i.e. x̄ > M > Z, is said to be a positively skewed frequency distribution.

In frequency distribution with positive skewness, the distance between the third quartile and the median is greater than the distance between the median and the first quartile. i.e. Q3 - M > M - Q1

In such a frequency distribution, the right tail of its frequency curve is more elongated than the left tail.

2. Negative Skewness or Negatively Skewed Distribution

The frequency curve of the negatively skewed frequency distribution is as shown in the above diagram-

A frequency distribution in which the values of the mean, median, and mode are in ascending order i.e. x̄ < M < Z, is said to be a negatively skewed frequency distribution.

In frequency distribution with Negative skewness, the distance between the third quartile and the median is less than the distance between the median and the first quartile.i.e. Q3 - M < M - Q1

In such a frequency distribution, the left tail of its frequency curve is more elongated than the right tail.

After learning the types of skewness lets also understand the “Tests of Skewness”

We know that the lack of symmetry of a frequency distribution is called skewness. To decide whether a given frequency distribution is skewed or not the following tests can be used.

(1) A frequency distribution in which the values of the mean, median, and mode are not equal.

(2) If both the quartiles i.e. the first and third quartiles are equidistant from the median, then such a frequency distribution is said to be skewed.

(3) If the frequency curve of the frequency distribution is not bell-shaped then it is said to be skewed.

(4) Frequency distribution in which the frequencies of the classes which are located equidistant from the middle class are not equal is said to be skewed frequency distribution.

(5) If the right tail or the left tail of the frequency curve is more elongated then the frequency distribution is said to be skewed frequency distribution.

Skewness and co-efficient of skewness

(Absolute and Relative Measures of Skewness)

Skewness: Skewness is a lack of symmetry in a frequency distribution. Skewness is an absolute measure and it is denoted by 'sk'. 

Skewness is not independent of units of measurement, i.e. it is expressed in the units of the given data.

Co-efficient of Skewness: The relative measure of skewness of frequency distribution is called co-efficient of skewness and it is denoted by 'j'. 

The coefficient of skewness is independent of units of measurement, i.e. it is a simple number free from the units of the given data.

Types of skewness with Examples. 

Symmetric:

If Q3 + Q1=60 and M=30, then state the type of skewness.

Ans: Sk = Q3 + Q1 - 2M

= 60 - 2(30) = 60 - 60 = 0

There is zero skewness. i.e. Frequency distribution is symmetric. 

Negative Skewness:

For a frequency distribution 3Q3 = 8Q1 = 4M =120. Then find its skewness.

Ans: 3Q3 = 120 so, Q3 = 40

         8Q1 = 120 so, Q1 = 15 
       4M = 120 so, M = 30

Now, Skewness = Q3+ Q1 - 2M 

so, 40 + 15 - 2(30) = -5

so, S= -5 

Positive Skewness:

The median and the mean of a data set are 52 and 55 respectively. State the type of skewness.

Ans: Here, median (M) = 52 and mean (X̅) = 55

Now, Sk = 3(X̅- M) = 3 (55 - 52) = 3 (3) = 9

Hence, mean > median, therefore there is positive skewness in the data.

Methods of determining Skewness and the coefficient of Skewness.

If a frequency curve of a given frequency distribution is drawn, then it can be known whether the skewness is positive or negative. But the numerical measure of skewness can not be known. Also, it is necessary to find numerical measures of skewness for comparison of two or more frequency distributions. For determining skewness and the coefficient of skewness following two methods are used.

(I) Karl Pearson’s Method

(II) Bowley’s Method

(1) Karl Pearson’s Method:

Base: In a skewed frequency distribution, the values of the mean, median, and mode are not equal i.e.  X̅ not equal to M not equal to Z. Also, the median always lies between the mean and mode. Karl Pearson’s method is based on this test of skewness.

Formulae: Skewness is the difference between the mean and mode.

i.e. skewness (sk) = X̅ - Z

The coefficient of skewness is obtained by dividing the above difference by standard deviation (S).

i.e. coefficient of Skewness (j) = X̅ - Z / S

When the frequency distribution is not unimodal or otherwise the mode is ill-defined, then mode can be obtained by the formula Z = -3M – 2X̅

Hence, when a mode is ill-defined then the following formulae are used.

Skewness (sk) = 3 (X̅ - M)

Coefficient of Skewness (j) = 3 (X̅ - M) / S

Note:

(i) The value of the coefficient of skewness given by formula 3 ( X̅ - M) / S always lies between between  -1.73 and +1.73 for any uni-modal skewed frequency distribution. 

This has been proved by statistician N.L. Johnson in the year 1951. But generally, in practice, the value of j based on a sample lies between -1 and +1 for skewed frequency distribution.

(ii) The value of the coefficient of skewness given by formula j = 3 ( X̅ - M) / S always lies between -3 and +3.

(iii) The mode is said to be ill-defined in the following situation:

(a) if the frequency distribution has classes of unequal length.

(b) if the frequency distribution is a mixed type (partly discrete and partly continuous).

(c) If the frequency distribution has been more than one mode. In this situation, the following formulae are used.

sk =  3 (X̅ - M) and j = 3 (X̅ - M) / S 

(2) Bowley’s Method :

Base: In a skewed frequency distribution, both the quartile Q1 and Q3 are not equi-distant from the median. i.e. Q3 – M not equal to  M – Q1. Bowley’s method is based on this test of skewness. 

Formulae: The difference between the distance Q3 – M and M – Q1 is taken as the absolute measure of skewness (sk). 

i.e. Skewness (sk) =    (Q3 – M) – (M – Q1)

 =     Q3 – M – M + Q1

 Skewness (sk) = Q3 + Q1 – 2M 

The coefficient of skewness is obtained by dividing the above difference by the sum of the distance Q3 – M and M – Q1. 

coefficient of skewness (j) = Q3 + Q1 – 2M / Q3 - Q1 

Note: the value of the coefficient of skewness (j) given by Bowley’s method always lies between -1 and +1. 

Comparison of Karl Pearson's Method and Bowley's Method.


1. As Karl Pearson's method and Bowley's method are based on different assumptions, the values of the coefficient of skewness obtained by the two methods may not be equal.

 

2.  The calculations are simple and easy in Bowley's method, whereas the calculations are not simple in taking more time in Karl Pearson's method.



3. The co-efficient of skewness obtained by Karl Pearson's method is more reliable than Bowley's method. Karl Pearson's formula off is based on mean X and standard deviation (S) which are the best measures of average and dispersion. 



4. Karl Pearson's method cannot be used for open-end frequency distribution. When open-end frequency distribution is given then Bowley's method is to be used. 

Points to be remembered while solving examples

(1) If it is not stated by which method co-efficient of skewness is to be calculated in the example, then use Karl Pearson's method. 

(2) If the frequency distribution is open-end frequency distribution, then use Bowley's method for calculating the coefficient of skewness. 

(3) In a given frequency distribution, the observations or the classes are to be arranged in ascending order if they are not in ascending order.  

(4) If the classes of a given frequency distribution are exclusive, then find boundary points for the corresponding classes for calculating median, mode, or quartiles. 

(5) If the cumulative frequency distribution of 'less than type' or 'more than type' is given, then convert it into an original frequency distribution. 

(6) If instead of classes, the mid-values are given then first find boundary points for

 each mid-value by the following formulae.

  Lower boundary point = Mid-value -  (Class interval / 2)

 Upper boundary point = Mid-value +  (Class interval / 2)

(7) If mode is ill-defined, then for Karl Pearson's method use the following formulae.  

sk =  3 (X̅ - M) and j = 3 (X̅ - M) / S 

(8) If a given frequency distribution is of unequal class interval or of mixed type i.e. partly discrete and partly continuous, then for calculation of mean and standard1 deviation by short cut method class interval (C) should not be taken.

(9) The value of the coefficient of skewness may be positive, negative, or zero.

Kurtosis

Kurtosis refers to the degree of presence of outliers in the distribution.

Kurtosis is a statistical measure, whether the data is heavy-tailed or light-tailed in a normal distribution.

Types of Skewness

In finance, kurtosis is used as a measure of financial risk. A large kurtosis is associated with a high level of risk for an investment because it indicates that there are high probabilities of extremely large and extremely small returns. 

On the other hand, a small kurtosis signals a moderate level of risk because the probabilities of extreme returns are relatively low.

Excess Kurtosis

The excess kurtosis is used in statistics and probability theory to compare the kurtosis coefficient with that normal distribution. 

Excess kurtosis can be positive (Leptokurtic distribution), negative (Platykurtic distribution), or near to zero (Mesokurtic distribution). Since normal distributions have a kurtosis of 3, excess kurtosis is calculating by subtracting kurtosis by 3.

               Excess kurtosis  =  Kurt – 3

Types of excess kurtosis

  1. Leptokurtic or heavy-tailed distribution (kurtosis more than normal distribution).
  2. Mesokurtic (kurtosis same as the normal distribution).
  3. Platykurtic or short-tailed distribution (kurtosis less than normal distribution).

Leptokurtic (kurtosis > 3)

Leptokurtic is having very long and skinny tails, which means there are more chances of outliers. Positive values of kurtosis indicate that distribution is peaked and possesses thick tails. 

An extreme positive kurtosis indicates a distribution where more of the numbers are located in the tails of the distribution instead of around the mean.

Types of Skewness

platykurtic (kurtosis < 3)

Platykurtic having a lower tail and stretched around center tails means most of the data points are present in high proximity with mean. 

A platykurtic distribution is flatter (less peaked) when compared with the normal distribution.

Mesokurtic (kurtosis = 3)

Mesokurtic is the same as the normal distribution, which means kurtosis is near to 0. 

In Mesokurtic, distributions are moderate in breadth, and curves are a medium peaked height.

Types of Skewness

types of skewness

Summary

The skewness is a measure of symmetry or asymmetry of data distribution, and kurtosis measures whether data is heavy-tailed or light-tailed in a normal distribution. 

Data can be positive-skewed (data-pushed towards the right side) or negative-skewed (data-pushed towards the left side).

When data skewed, the tail region may behave as an outlier for the statistical model, and outliers unsympathetically affect the model’s performance especially regression-based models. 

Some statistical models are hardy to outliers like Tree-based models, but it will limit the possibility to try other models. So there is a necessity to transform the skewed data to close enough to a Normal distribution.

Excess kurtosis can be positive (Leptokurtic distribution), negative (Platykurtic distribution), or near to zero (Mesokurtic distribution).

Leptokurtic distribution (kurtosis more than normal distribution). Mesokurtic distribution (kurtosis same as the normal distribution). Platykurtic distribution (kurtosis less than normal distribution).