How do i come up with a null and alternative hypothesis for this statistical problem?

2. A lady reads a new diet program. She wants to adopt it but unfortunately, following the new diet program requires buying nutritious, low calorie yet expensive food. She thus randomly selected some of her friends who already adopt the new diet and asked them about its effectivity. She intends to adopt the new diet only if the percentage of people who claim that the new diet program works is greater than 60%.|||H0: p ＝ 0.6


Ha: p %26gt; 0.6


*remember to define p, the population proportion|||The hypothesis should revolve around whether the new diet works or not - and you have to define what is meant by "works"... that is ... what are you trying to find the probability (in your case 60%) of ? How will you measure it .... one Alt Hyp would be "Women who adhere to a diet of nutritious low calorie foods will maintain their weight during a period of 1 week". %26lt;-- that's not great wording, but it should give you an idea (you know your stats project better than I do ha ha)... Note : your hypothesis might be that the lose weight rather than maintain their weight .... or that they will not gain more than 10lbs - etc.. get as specific as you think your "theory" is ..


As for the Null hypo... any hypothesis as stated, can be changed to a null hypothesis by adding the word "NOT" ... so in the above case, the null would be "Women who adhere to Diet X will NOT maintain their weight during a period of 1 week".


Really what the Null hypothesis stands for, is that the variable of interest has no impact.... ie that nothing changes (ie. the diet doesn't work )


Using stats facilitates in calculating the probability of the hypothesis being true (rather than proving it) - in most cases, if there is a 95% chance that the alt hypothesis is true, then it is considered significant... In your problem - it seems that 60% would be enough of a probability to accept the diet. (Note : any diet would have a 50% starting chance of working anyway)...